F12 design and development

Righto, go your hardest!

Can I get a scuba set with it? <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

Folks,
The simplest and easiest ply hulls you can build would be deep skinny symetrical bannana shaped hulls.
No c/b and no skegs and bugger all tooling up.

Windrush produced a 12ft surfcat in glass with spade rudders that sailed quite good (even upwind) with this style hull and the kids at my sailing club and some of the parents used to have a ball on them. Sometimes sailing 3 up.

Dead simple to do in wood.
If I was doing it in timber I would glue 2 lengths of ply to a 2 inch wide keelson of cedar.
Halfway up the hull sides would be a stinger each side full length.
Cedar props between the stringers to give only slight curature. (As perfectly flat panels are not very stiff.)
The deck would be sold foam with a layer of glass laminated underneath. Shape the top of the foam to a preset deck curve and a couple layer of glass on top.
This would not only be a deck but also provide floatation.
The way you shape the deck will dictate how asthetically pleasing and modern the boat looks.
I've not done the calcs but my guess would be maybe 12kg per hull. Just a guess.

One off would probably take several weekends but if you set up production line style you would probably average a pair of hulls per weekend.

Quick , easy , dead simple and dirt cheap.

BTW:- As the panels are essentially flat you could build these from any material you like but some materials may need a bit of tooling.

Regards,
Phill

I started sailing on a 12 ft surf cat(windrush) When I was still in nappies.
31 Years later I got another one($250)and took my two year old out on it. The one I started on (sailing every school holidays) is also in the back yard. These were great boats. I have two boys 3 and 1 and the boats are there waiting.

See also posting ;

http://www.catsailor.com/forums/sho...;Number=95089&page=&vc=1

wouter

On the subject of simple fast build hulls, this is something I put together this time last year, never got round to making it, maybe I will this year. The idea was a 10ft boat hull that could be built from a single sheet of 3m x 1.5m ply, it could easily be scaled up to an F12 , in fact I have a parametric CAD program that will produce drawings of any size you want.




The hulls are asymmetric and shouldn’t require a daggerboard. The nice thing about it was the minimum amount of cutting required to make the panels.

The attached PDF file is a hull template that you can print off and make yourself a model. The two sheets contain identical panels, just layed out on the sheet in different ways. The first sheet is meant to show that the same cut produces both side panels, i.e. two sets of side panels (for two hulls) can be created with just 5 cuts instead of the usual 8.

The second sheet is to aid model building out of a material that can be folded such as card or paper i.e. the three horizontal lines in the centre of the panels should be folded not cut. All the panels are flat with the exception on the four outer leaves of the side panels which require some gentle bending.

Print it out and try it <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />


http://4hulls.googlepages.com/flatpack3.pdf

Gareth
www.fourhulls.com

Some more views







And an edrawing file that you can view a 3D CAD model with a free download from

http://www.solidworks.com/pages/programs/eDrawings/e2_downloadcheck.html

http://4hulls.googlepages.com/F10.ePRT

Gareth
www.fourhulls.com

The beams would spend a lot of time trying to drag extra water up wind.
Smaller Paper Tiger would do job and use less than one sheet of ply amd beams are just box section bolted.
This desgin could easily be shrunk to ten or twelve but realy we want to use what advances are appropriate since '75.

I have been thinking about this alot and talking to an older neighbor who usually has alot of good ideas about alot of stuff.

Here are a few things that he pointed out.

-The boat must be simple ( we already know this, but simple to us isn't simple to a mother trying to put this boat together for their kid.)

-The boat needs to be storeable in a very small area. And it needs to be able to fit through a gate so that it can be put in a backyard very easily.

- It doesn't have to be fast, just give the sense of speed. Also it needs to be able to be sailed in very shallow water.

- Every connection needs to be done with the quickest thing possible. No pins and split rings, they are difficult to use for anyone with bad eyes.

-The sail needs to be rugged. If it gets left outside for a couple of days it still needs to be okay.

-If we are going for car toppable then we will have to make sure that a rack is made that is very easy to use.

He has some other ideas and comments about the idea of a small cat. He has a few grandchildren and said that if some company starts making this boat he would be willing to buy one or two. Granted he has alot of money and likes to spoil his grandchildren but I think more of these would sell then some people think will be.

Thanks Gree2056,

I've not mentioned how to transport the F12 yet but it is under consideration.

I would really like to keep the hulls, beams and tramp attached at all times as then rigging and unrigging will be very easy indeed. I'm hoping that a 12x6 foot platform will be small enough to be left fully assembled. It will pass through a gate I'm sure, especially if the gate is low and the boat is on top of the car. <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

Seriously I'm thinking about a setup where the dolly remains under the sterns of the boat while it is loaded onto and off the car. The bow can then be layed on rollers fitted to the roofrack and the boat can be push onto the roof by the rearbeam while lifting only 15 kg as the bows/rollers carry the other 15 kg. In the garage the platform could be hoisted to the roof with roofrack remaining attached.

Stuff like that. It is under consideration.

Again the rigging is very simple, currently there are no pins or rings. Blocks stay on the sail and boom and you only need to run the sheet through the blocks after stepping the mast with sail.




Plain dacron will hold up for many years despite heavy abuse.


Wouter

Actually what I meant by getting it through a gate is that these people who buy the boat are going to have to store the boat somewhere. In alot of neighborhoods they do not allow you to store a boat beside your house, so most people will have to store it in the backyard. A boat on a trailor will not go into a backyard. I was thinking that this boat might break down in to something pretty small but after thinking about that it makes things a mess during assmebly.

I like the rollers idea, that would allow almost anyone to haul the boat. What made me start thinking about the transport was the kids that live across the street. Their mother is raising them alone, she is always hauling them around to soccor games and what not, so if she is willing to do that she and other mothers would probably be willing to haul the boat out to the lake. Single mothers have to be able to get their kids on the water without much more trouble than they take them to soccor practice.

If this boat is really going to take off and kids all over start sailing it we will have to think out every angle.

I am glad to see people working on this. More people out on the water will create a higher demand for performance boats. Hopefully this will cause some companies to create inovative new designs.

I think that a 12ft version of Jon Montgomery's Catapult would be very suitable. It would be quite narrow with the hulls deflated, but not taken off the beams. A quick pump, mast up, sails on and away you go <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />
This is quite a fast design - I used to beat Condors and Hobie 16s to the windward mark, racing a standard 5m Catapult. http://www.catapultcats.com

So everything we say keeps coming back to these inflatable cats. Is that the way to go? It would be really nice and be super light and simple. But for some reason I don't see it winning over tons of people.

Also the aquacats might be okay. I know they look so bad they don't even catch crap on here but when push comes to shove they are cheap light and easy, maybe a different rig on one would do it.

My interest in building from scratch is land yachts. Something that could be built and used during the winter. The more I thought about it the more I realize I'm a warm blooded person. And if it's warm enough to sail, may as well be on the water.

For me building a three sailed boat is somewhat selfish, cost prohibitive, would end up not being finished before summer, and probably not a smart move for someones first boat. But a simple 12 footer seems doable.

I've got enough parts laying around for a rudder system. I see the sail as the largest single item expenditure and I'm hopeful to be on the water for less than $3K.

I think aiming for three thousand is a little high. What if we started shooting lower. I understand that the sail and other hardware is going to be expensive but it seems like this thing could be built cheap.

Here a first part listing.

I made this to get a feel for were I was in the way of weight, but it may also give you some idea of the costs shall be.

It must be noted that I have 0.5 kg reserved for shackles, rings and other chandlery stuff. However at this moment my design has not used a single one of these yet and it is pretty far developed. Amazing what you can do with lashings, beads and figure 8 knots.

The only part not further specified are the hulls themselfs. I really don't know how much money is involved there.





25 kg for everything other then the bare hulls. We are on a right track here. I think I can reduce the weight of the mast a little further as well. But I'll have to check that.

Wouter

Wouter I would like to say that what you are doing is impressive.... but remember we are going to have kids sailing these things. Those hulls are going to be very light which I hate to say it but light hulls are usually not as tough as heavier ones. I am not saying that they couldn't take racing and stuff like that but I am not very far gone from those younger years and I know that kids are hard on stuff that they own.

You are corrert of course.

At this time my main focus is to get the stuff other then the bare hulls as light as possible. Any savings here can directly go into heavier hulls.

I would like to make the hulls out of glass layers and core-matt material. Looked briefly at twinex, but just like rotomolded hulls these are practically out of the reach of homebuilder or even a small company make a small serie of hulls (start-up)

On the other hand, don't underestimate the strenght and dent resistance of 4 mm ply on such short hulls. Especially if covered with a single layer of glass it will be surprisingly abuse resistance. I'm sorry to say that my crew did test that aspect on my F16 with her trapeze hook. Hitting the deck with the hook first will all of her weight and then sliding off with hook scratching at the deck still carrying all her weight. Now she is pretty light 58 kg I think, but still the damage was mostly visual. I now have a 100x5 mm scratch on my decks that you can feel be moving your fingers over it but the true depth is probably only 0.5 mm. The boat is fine beyond that.

It is also my intention to cover the keel line with a strip of aluminium to prevent wear of the hulls being dragged along the beach and stiff. With a V-ed keel this should also protect the hulls against most submerged rocks. In addition I'm looking to make the hulls easily repairable so small holes are hopefully not a serious issue.

And at some time we have to trust the kids not to use the boats as bumper cars. I've seen 8 year olds being exceptionally attentive to optimists overhere. I guess it all comes down to how you raise your kids. Lasers and optimists aren't bullet proof either.

And like I say all though this thread. lets give it a try and see how it works out. There is no point in giving up on something before you really do know whether it will work or not.

Everybody keeps saying this and that won't work, but do we really know that ?


Wouter

I don't quite understand why, if you are coming up with a whole new design that is for children, you would want to make it a Formula instead of a One-Design. One key to success for kids' boats is that all the boats be identical so they know success is dependent entirely upon their skill, not on their boat being a little bit better or lighter or faster than the other boats.

And since parents will be building the boats (theoretically), it would just become an adult competition to see who can build the fastest boat. How does that benefit youth sailing? And wouldn't it be sending the wrong message to the kids?

That is an excellent point Mary.

I'd envision a scenario such as this. A group of sailing club parents pick a home build design of a degree of difficulty they want to attempt, within a certain budget, such as a simple cookie cutter design, of hulls being built over a weekend specifically for the purpose of having three or four similar boats for the youngsters, within that club, to play with.

As you have eluded, nothing is keeping another group from expending considerable effort and time in building a more complex design.

That in itself precludes the two neighboring groups from getting together for a competition. Wow, we're really taking a LOT for granted here and moving this forward quickly.

As one primarily on the side lines of this I can only hope for a hull design that is modern and performance oriented, but is easy to build, definitely that is a trade off.

I can also predict some argument here on the degree of difficulty involved before a first "kit", if you will, is decided on.

What is to preclude naming specific hulls, and emphasizing not letting adult thinking to spoil children's competition, allowing competitions to be of specific kit designs within the formula? A part of class association rules? Possibly the box rule can somehow limit physically the capability of the hull, i.e. large radii and such? But how would you measure this? Is there a "junior" F12 set of rules and an "open", traditional, developmental, F12?

Whew!!! Again thanks.

This is easy to answer.

For the sake of the argument I shall not press home the point that the F12 is not specically for kids, but more for any person in the range 40-65 kg. This will also include teenagers and small adults.

But back to just youths.


One-design boats simply aren't fair to youths.

First of all how One-Design are youths anyway ?

If they aren't then why should the boats be ?

Allowing some freedom in adjusting the stiffness of the rig and sail cut will allow some of the inequalities between kids to be corrected. It has been shown many times that the classes with the highest sensitivity the crew weights are the OD classes.

It is in my personal opinion a downright myth that differences in material (under formula rules) are significant when compared to differences in crew skill. It is incredibally easy to show how different designs result in maybe 1%-3% difference in performance while differences in crew skill will easily result in up to 30% difference in performance. And we should not forget that aging boats will sails older then 2 years will also be about 1%-3% slower around the course. In short, if your kids needs to sqeeze out those last 1%-3% of performance then he needs to by new gear every two years anyway, irrespectably whether he is sailing in a formula class or OD class. If that is the case why then accept the downsides of OD classes which are :

-1- expensive replacement parts, sometimes even of mediocre quality.
-2- not allowed to source your own (local) suppliers of parts or make them yourself.
-3- no continued (but slowed down) development, meaning the class will grow outdated in 10 to 15 years time.
-4- less builder support as only one builders needs to do everything. Why do formula classes come up so strong ? Because several builders and suppliers are pushing it in one coordinated effort.
-5- A nightmere scenario when having to check boats for compliance at events. EVERYTHING needs to be checked.
-6- Either the design is very good but impossible to homebuild or it can be easily homebuild but everybody is sailing bathtubs.
-7- OD doesn't allow quick and dirty homebuilds to allow easy and inexpensive acces to sailing.
-8- Problems when US builders are not using the SI unit system. Is 1/16 steel wires the same as 3 mm steel wire ? Ask the Hobie 16's how such a thing lead to a right protest frenzy at one event. At one event in the 80's the crews were checking eachother boats with caliphers trying to spot US stays and protest the owner out of competition. That will be a good behaviour for your kid to learn.




That may be true to some small extend, but how is this different from your kid chosing the right tennis racket for himself or the right mountain bike or even the right track shoes or skis/snowboards?

Why do we in sailing land think that chosing the right gear for your body setup and preference shouldn't be a normal part of competing ? In by far most sports it is. A top level tennis player will replace his racket 4 times during a game ! If you choose the wrong mountain bike gear setup for the course then you have a problem.

How many one-design cycling events do we have ? If you go and play tennis, do you make it a point to play with the same racket ?


As such having to choose and optimize your gear to suit your body and way of sailing is actually sending the right message to your kids.

And it does benefit youth sailing by being.

-1- cheaper
-2- better available
-3- better developped
-4- better promoted by a bunch of builders (future)


But I think that this has been discussed many times over Mary. You do seem to ask this question a few times a year.

Doesn't the wave class allow different mainsails ?

Wouter

Thanks Wouter,

Something in the back of my mind was saying how could only the hull shape have that great a significance in speed, when weight and size of the sailor will be varying wildly.

Of course us adults can get all wound up in thing such as whether 800, 1200 or 2000 paper is sufficient for our boards, when the nut on the tiller has exponentially more affect on performance.

OF COURSE, we do. The Wave is a one-design boat. So just as with most one-design sailboats, you can get your "motor" cut flat, medium or full to accommodate your crew weight and/or your normal sailing conditions.

I don't see how that has anything to do with modifications in platforms.

You have an opportunity here to create a little, one-design catamaran for kids, that ALSO can have sails cut to suit weight -- just like the Tornado. And the home-builders could make their own sails, too, and try out different fullnesses and shapes within the class sail measurements.

I understand both points of view on this issue, but think that if you are going to get parents and more particularly yatch clubs and kids racing programs involved and "buying" into it, OD is probably an easier sell than a formula approach. The Tornado itself is still a development class, just with tight restrictions as to the development progression. The hull shape is closely defined, but there is around a 5-10mm varience that can be used to alter the shape and performance of the hulls. As to the fact that 99% of the boats raced are from one builder, it is virtually OD. Back to the point though, OD for class development is an easier sell to youth programs.

I wonder if that is the variance allowance that was put in the original rules when the requirement was that the catamaran for the Olympics would have to be able to be home-built. Obviously, it would be more difficult to build a boat in your garage to the same tolerances as in Marstrom's factory. So maybe they allowed a little slack in the rules for the people who could not get their plywood bent quite to the right shape?

We need to decide what group we are aiming for. I have heard everything from youths to teenagers and small adults. IT will be hard to market to both of these groups.

As for OD vs Formula, just think about it if it is OD. Some kid buys this boat cheap and has to replace some worn out part. To buy this part new costs 100 dollars while he can go out and find one that works at the local hardware store for 15. Now he can't race, that isn't what we want. I have heard horror stories of people being turned away from Hobie events because of tiny little pieces that didn't match.

Also I think that a glass over ply seems like the best idea and with the strip of aluminum along the bottom of the boat it should be fairly resistant to most things.

No, no, no. <img src="http://www.catsailor.com/forums/images/graemlins/shocked.gif" alt="" />
Don't confuse one-design with one-design-single-manufacturer. Those are two different things entirely.

Interesting thread but I'm not sure that it will catch on. Kids want bang for bucks, that means hopping onto a fully rigged boat and stepping off at the other end, now you and I think that may or not be the case but from experiance of the kids of today, thats the sad truth. If the set up time takes longer than their Play Station then you are onto a loser. Parents are mainly to blame as we have become so used to a service led society that with our too limited spare time, we want to just get out there ourselves and pay somebody else to teach our kids.

As much as we would like to think that people will spend many hours building a boat I can tell you that only the dedicated parent will make them and he / she will be mainly in it for the thrill of " making the finest and best design" he can, which lends nicely to the freedom of a Formulae class. Kids are going to be only the end user product of a parents desire to build a boat.

As to halting the general decline in sporting activity in our kids then I'm afraid we need to look at our lifestyles first, sort out that and give ourselves more time to paricipate with our kids and I would bet that the kids would then be willingly to go sailing as there are a lot of good times to be had whilst sailing.

gree,

Check the parts list. The Dotan stocks and rudders will be about $1K or better for the pair. A new sail may be $800. All will add up fast. Conversely, I have several Hobie rudder assemblies from dead boats, will they be as easy for a ten year old to operate as Dotans? No, but they're "almost" free. Some searching the windsurf clubs may net a suitable sail for next to nothing as well.

You're right, it could be built cheap.

I understand that the stuff will add up fast. But if this boat is going to be a boat for the masses then it has to be cheap!
The designers of this boat need to aim very high (low price) that way if you miss the mark the boat is still cheap.
This is what needs to be done if the boat is to be successful.

Has anyone mentioned A-class? The boats are extremely equal in performance, but it's a formula class if ever there was one.

Did you get a quote on that ?

But considering that the rudders both act as rudders and centreboards on these F12's an investment if proper gear will be well worth it from a performance point of view.



That is for a class 5 landyacht sail from a very respected sailmaker like R&J sails (supplier of champions in the landyacht business).

You are not paying so much for the materials or even the labour but for this company's expertise and ability to build winning sails.

Building these sails yourself should really be won of the more simple tasks if the panel layout of decent sail would be known.

In the coming weeks I may look very closely to my own R&J class 5 sails and see how it is build up. If it is simple enough then we may be able to adjust it to suit the F12 boat (more draft in sail)

Personally I wouldn't hesitate making my own sail if I knew that I had the panels dimensions of a decent sail. Dacron cloth is not that expensive and the building method is just basic sewing.

Wouter

Currently alot of money is taken out of the design but not using any specilized gear like traveller rails, cleats, blocks, shackles, etc. Surprisingly enough this does safe a bundle.

But in order to make it really cheap you have to accept doing alot of building yourself.

Expecting somebody else to build the stuff at some reasonable quality and then only pay "ice-cream" money is simply unrealistic. The guy doing the labour is doing so to pay the morgage, childrens education fund and his own retirement. Like that it will never be dirt cheap.

I'll show you more of the design shortly

Wouter

[/quote]
I wonder if that is the variance allowance that was put in the original rules when the requirement was that the catamaran for the Olympics would have to be able to be home-built. Obviously, it would be more difficult to build a boat in your garage to the same tolerances as in Marstrom's factory. So maybe they allowed a little slack in the rules for the people who could not get their plywood bent quite to the right shape? [/quote]

That may be, but part of the reason truly was to allow differences in hull shape. Ie, Yankee Laminates Tornados had a finer bow entry and was pushed to the maximum tolerances at the deck line. This gave the hulls at the bow more volume with the thought being that it would create greater bouyancy. So you basically had four different designs, even though minor between Marstom, Sailcraft of Canada, Reg White and Yankee Laminates. It is too bad that the home built loophole has been closed for the Tornado Association. I think that I built one of the last allowed home-built Tornados.

No. Based on pricing "comments" from a Dotan retrofit post found via google (don't know how old) and roostersailing


OK, I'm trying to help gree identify where this $3K number is coming from.

This setup in indeed the Dotan setup I was looking at.

£236.00 = 350 euro or 457 US$

So 700 Euro c.q. 914 USD for a pair.

That is quite an attractive pricing.

And the rudders will be the most expensive part on the boat after maybe the hulls. For that price I would consider buying these rudders that is if they are up to specs and stiff. As I wrote earlier the rudders will replace the daggerboard to a significant extent so a proper rudder design will go a long way in improving upwind performance.

I've noted this info down in the design paper thanks for looking it up.



Ohh, sorry, but only coined the 3000 USD mark because that is what I'm trying to get to. The onderlaying thought is that Vanguard sells the optimist dinghy for 2500 US$ and I want to stay close to that. Therefor I personally consider anything under 3000 USD a succes for the F12. It is not based on real costs yet. It is just a design goal at this time.

Still it is looking good on this aspect.

Does anybody know what sheets of 4 or 3 mm ply cost in US$ and Euro, highest quality ?

Wouter

Wouter,

If I remember the price correcty the BS1088 was 14 euros / m², so one sheet was ~42 euros. This propably has some sort of Finland tax included, so I assume that it should be lot cheaper in some other country.

--
Valtteri

Two words - Arafura Cadet -!!!
Little brother to the Arrow, home made ply hulls from plans available from the Arrow association, 11' long, (I think from memory 6’ wide), sloop rigged, goes like the clappers, takes an unbelievable hiding and just lasts and last forever, has been a successful class for over 40 years (they have had "national titles" every year in conjunction with the Arrows) and has just recently started to grow in numbers again, is commonly roof racked and stored tied up under the roof of a garage or shed. Seems to me that you are trying to reinvent the wheel? Sailed one up by an adult or by two juniors, and CHEAP.

I googled the Cadet and the first link was to Phill's website. He even talks about building it there.
Cadet

Phill is one of the ones wanting to do this, so I assume he knows why.

The Cadet certainly proves this approach works (at least in AU). The choices of home build boats there is astounding.

What I see in comparison to the Cadet
the F12 has;
no trapeze, no side stays, no fore stay,
no separate downhaul, no mast track and halyard,
no jib and halyard

...a very simple, and short, setup time. Hopefully that is an appealing goal to US homebuilders. A boat that can be on the water in a flash.

I wonder what does the Cadet weigh?

BS1088 4mm x 4' x 8' sheet = $55 USD
BS6566 3mm x 4' x 8' sheet = $45 USD

Oakum ply in stock in New York
will not ship <img src="http://www.catsailor.com/forums/images/graemlins/confused.gif" alt="" />

Those Afura hulls look close enough to "good looking" to warrant considering them for the F12.

All the other stuff however will be changed. Reasons :

F12 is still cheaper
F12 is still simpler
F12 is still one or two steps easier to build and rig.

I've got the rig pretty much finished now and it is a really nice concept.

We just need to find easy to build hulls that do look nice at the same time. How easy is it to build the afura cat hulls ? Also 100 hours as the Paper Tigers hulls ?



Currently no shackles have been used in the design, actually one needs to get only the following from the chandlery :

-1- 1 ratchet block (no cleat)
-2- 3 simple 30 mm sheeve blocks
-3- 1 simple 30 mm sheeve blocks with becket
-4- 10 saddles (eyestraps)
-5- about 6 mtr 6 mm or 8 mm sheetline (swiftcord)
-6- about 4 mtr 4 mm racing dyneema
-7- 3 universal joints

All the rest is just lashings and knots.

This my friend equates to CHEAP, cheaper then the afura cat that does have quite a lot of chandlery shop.


Additionally, everything is home made EXCEPT the Dotan rudders and rudder boxed, but the rudder setup could be can be homemade as well.

Wouter

Looking at the Cadet photos on Phil's site made me come to a realization. A kids boat needs to look like a toy in order to be attractive to a kid. An Opti certainly fits the bill as does this Cadet.

Is there a particular stumbling block to building this concept you proposed on the Youth Recreation Trend Page 12 last week?
The F12 simple hull? (I could not transfer the .gif) Now that is definitely a modern look.

Easy to build? In 1979 I built a complete set of hulls over three weekends, and the hardware, mast, sails etc, are also "small" and as cheap as you can get. They cerainly aren't "rocket science", but a great fun little machine that gives great satisfaction to sail (and race) and they are light enough that one person can "roof rack" them by themselves (without getting a hernia). We bought two of them a few years ago for an association as a "trainer" for members of that associations kids and we picked up both of them for A$500.00 (A$250.00 ea) second hand. Rigging and derigging takes about 15 minutes (if you don't rush it)

Hi All

Firstly, the money that would be spent on the Dotans, would easily bridge the gap when comparing the fittings on the proposed F12 and the Arafura Cadet.

Don't get me wrong but the fittings list posted earlier seems to be pushing the cheap side of the deal, for example, the telescopic battle stick.

I can't find any info on the Impara Cadet anywhere, except for a past yardstick listed with the Victorian Yachting Council, I will try and get to the club and take some photos, it really does look like a 12ft Mosquito, great little boat.

Regards

Hi all,

The Arafura Cadet national championships were sailed here in Adelaide last week & while only 7 boats contested, the quality of boats is high.

The platform only weighs about 36kgs ( class minimum) & is only 11 foot long - so a little short for F12.??

I learnt to sail on one of these fun boats as an 11 year old 25 years ago & they are the only real training boat for young kids in this country.

Darrly is correct that if you drove around the suburbs here you might spot one stung up in the garage unused.

I currently have a set of new hulls, beams & mast in the roof of my shed ready for when my 9 year old is ready to try sailing by himself.

I have a PDF copy of the class rules if any body is interested & i'm pretty sure the class association sells the plans for about $40 au EACH.

Marcus

Sounds like a perfect lake boat. While I'm going to be heavy for it, I'm going to use this opportunity to learn the basics of boat building AND have something that I can just throw on the roof rack and go sailing in less than an hour from garage to launch. Perfect for those late afternoon hookey sessions.

Only thing I'm gonna want to do is throw an MX RAY spinnaker on it <img src="http://www.catsailor.com/forums/images/graemlins/smile.gif" alt="" />

Yes, me wanting to allow these hulls to be build under 50 hours of work. This on the advice of phill. If you guys are really building a few of these then you better be able to pop a few out over the winter. Methods like tortured ply take to long.

I think I have a few solutions now. I'm down to only 3 "filler and tape joints". If a series is build then the prototype will be "filler and tape joints" taking a little time to build but after that the original hull can be used to make joints using shaped rods and that should really cut down on building time, allowing a group to pop out hulls rather quickly.

Also I'm now back at normal life responsibilities and so can only work on this design maybe 4 t 5 hours a week instead of 30 to 40 hours a week.

Here a more profiled look at the hulls (called 5 panel chined wave-piercer) that I think we can use.



Wouter

There are two luxuries on the F12 as given now.

A single ratchet block in the mainsheet system to make holding the sheet more comfortable and a telescope battle stick tiller extension. However both can be replaced by respectively a normal block and a plain alu or glass tube covers with some grip material. Afterall this boat has no stays or a trapeze so a one-piece tiller extension won't stick out very far or hang up on the stays/trapeze lines. Like this the cost is maybe only 40 bucks.

I did a quick run of costs and it is way lower then I expected it too be. I need to be a more detailed calculation of cost but currently I'm just below the cost for a new US optimist dinghy by vanguard and that includes the dotan rudders and ratchet block. The rudder setup is now about 35 % of the total cost, with the professionally build R&J sleeved sail at 30 %. Those are the two most expensive items but can both be homebuild significantly cheaper.

Wouter

Wout,

is the hull design finished? If so could you publish your drawings so I can get them to a plotter? <img src="http://www.catsailor.com/forums/images/graemlins/smile.gif" alt="" />

Also, would a simple H14 rudder setup work on this?

The F12 looks like fun class, I might be interested in building one if you allow more "Bladish" hull design in the rules. I have built my Blade following the plans and after this experience it should be fun to try on my own design or experiment more on some other design (if wave piercing design is available).

Wife has to agree to take F12 catamaran instead of kayak that I promised to build her next winter though <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />

--
Valtteri

Regarding the rudders, I had the same scenario in mind, in the interest of getting on the water quickly. (However, I'm a big advocate of NOT canabilizing old boats, especially an existing H14, even if not in "race" condition, that a kid could enjoy).

I haven't had a chance to compare the dimensions of the Hobie rudder to the Dotan 20. dotan 20
If the area is close to the same, the 11 year old girl, who currently crews with Grandpa in 16A, can probably handle the Hobie system. The other two children (a 6 y.o. girl and 8 y.o. boy) that I'd like to have sail this boat, currently sail Prams and I think they'd struggle with the Hobie rudders.

Phill eluded to a homebuild ply box and rudder here somewhere?

Trey has more rudder systems laying around collecting dust that are orphansed from their boats, and I'm not building this for a 11 year old girl, I'm building it so I can putz around the lake when I'm bored at work and need to get out <img src="http://www.catsailor.com/forums/images/graemlins/smile.gif" alt="" />

It is finished in concept. I'm now working out the dimensions of the panels and the curves on the seams. But I must caution everybody that a large extend of hull design is where to place the volume and how to curve the keel-line. Those are things that need to be optimized by prototyping a boat, sail it and then adjusting the hull shape. Probably after the 3rd iteration the hull will be as we want it to be. This will take about 12 to 18 months if we work at it hard.

I don't have the resources to prototype the boat myself at this time so other people will have to do that. Also I think I've done my investment already in working out the design. I'm happy to see someone else do the prototyping and then I can adjust the design based on the feedback.

One alternative would be to buy the arafura cadet catamaran plans and build those hulls. Then you are assured that the hullshape is close to what you want and that the hull construction is dependable.

But if you are a little bit more adventurous then the new 5-chine wave-piercer hull is your candy.

I will be a few more weeks till I have figured out the right keel curve and bulkhead frames. I'm lofting the 5-chine hull in simulation software. But the design is coming, you can be assured of that.



I don't see why not ?

If the rudderboard area is large enough then by all means use any catmaran rudder system that is available to you.

The only other requirement of the rudders is that you should be able to balance them, afterall we are using the rudders as daggerbaord replacements and so unbalanced rudders will have very heavy weather helm feel.

Wouter

Certainly in the initial phase I shall not limit any hullshapes. Lets see what we all together come up with over the timespan of the next 2 years. After that we may settle on a signle hullshape if that is required.

I'm convinced wave-piercer shapes are possible.

Wouter

Trey,

What is your body weight and length.

I'm not garanteeing anything bit maybe I can just design your hulls to carry a little more weight.

Wouter

I'll do it, as I'm more interested in the building process than the actual performance.



Sounds good. I'll shutup until then.

EXCELLENT !

That is just what we need for the prototype.

Till then.

Wouter

If anyone's interested, I've worked Wouter's idea into this:

(Image deleted. See attachment.)

Maugan,

Need a source of oakum ply that will ship. Seems most, if not all, wooden boat building suppliers are on the coasts. Have you done any sourcing yet yourself?

You may want to contact one of the kit kayak companies that buy in huge volume, they might be able to give you the name of a good supplier. Do you think this hull would be built using the sticth and glue method that the kayak kits use? It's supposed to be very easy but I have not tried it yet. Maybe, once the design is finalized, we could get one of the large kit kayak companies to put together a hull kit with all the wood and precut panels? http://www.clcboats.com/boats/sharpie.php

For Okoume or Merranti
try Boulter Plywood in Mass. they ship country wide and stock everything plywood. Wonderfull to deal with

http://www.boulterplywood.com/

4x8 3 mm is 39$ each, 4 mm = 45$

I could see me building one of these suckers for screwing around on a local lake

Eric

Thank you Eric,

By far these are the most reasonable suppliers.

I noticed for an additional $59 they will scarf two sheets to make one 4' x 16'. Shipping penalty for this oversize length would be an additional $30.

Any merit to 4' x 16' stock?

At least if you build Blade F16 you don't need to do that yourself <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />

Seriously the bulkheads could be done from the 4' and deck from side of the panel if designed carefully. This way it should be just plotting and then cutting thus saving the trouble of joining the panels.

--
Valtteri

Good source for cheap fixed or telescoping tiller extensions is to use a fixed or telescoping paint roller handle - available at home centers in a variety of lengths/materials. Not very bling, but certainly up to the needs for this boat.

The 5-chined wave-piercer will be "stitch and glue" for certain if building only 1 boat.

What I'm trying to do it design it in such way that only 3 joints need to be stitched-and-glued with the remaining 2 joint being a simple screw and glue after routing the joint rod to the right angle.

And if more then one boat is made by a builing group a joint rod can be made for all joints allow all additional hulls to be simply "screw and glue". This should save time. Another idea I have it to have one guy build a prototype and make an angle tool of this hull for all joints and have him sell routed joints rods for all chines to other builders. This would allow all other builders to save time and would recoperate the cost of the prototype. Definately a win-win situation.

I hope this answers your question, Tim.




That is an excellent idea Tim.

The already offer another multihull, the "Pacific Proa" http://www.clcboats.com/boats/pacificproa.php

I think I will contact them after the design is finished and sell these plans through them.


Wouter

Of course you can have them make the scarf but not glue it together yet.

That additional saves shipping charges and you only need to spend a little time glueing the platse together yourself.

Also less risk of damage during transport ? Afterall a 6 x 2 foot package is alot easir to handle then a 12 x 2 foot package.

Wouter

Good idea,

Noted, thanks.

Wouter

You got that right, I would personally LOVE to have one of these F12's for the days and evenings when I don't have enough time to rig the F16. In my case that would be most weekday evenings during summer.

I had been thinking about buying myself on old laser 1 dinghy but experiences held by other laser owners at my club say that the surf on our beach make going out and coming back in difficult. A catamaran is much more suited to traversing the surf, sandbars and associated breakers.

In my case I will just clip my F16 rudders and tiller extension to the back of this boat and use one of my spinnaker sheet autoratchets for the mainsheet. And of course I just use my class 5 landyacht mast for the sail. Hell I got enough spare blocks and bolts laying around to complete fit out this boat as per current plans.

Yes, I think I'm designing a boat that I will be sailing myself as well.

Preliminary drag/saildrive calculations show speeds beween 9 and 14 knots both upwind and downwind.

OHHHHH yeah !!!

Wouter

Having attended a seminar on stitch and glue building by Chris, I can tell you he is multihull fan. The Proa design is very interesting, and I had asked him if he would ever consider a kit or plans for another multi (I was thinking of a cat based on the basics of the Proa main hull). He didn't rule it out, but had nothing planned, as something like that might be bigger than a practical kit. This, however, may just be the thing that gets their interest. If nothing else they may be willing to share some tips that would help the design be a success from a mass building sense.

Here's the linesplan to the drawing I posted earlier:






I can tweak the design very quickly to accommodate any changes that Wouter or anyone else wants.

One little thing about that design above, I know little kids will ram those things into each other and the dock, etc. so how about making the bows plumb top to bottom instead of pointy at the waterline? That would spread out the impact stress and hopefully NOT cause holes in the hull of what ever they hit, and protect the bows of the hitter as well.

Also, I asked them (CLC) about doing a wooden Blade F16 kit but he said it would be too hard to it as tourtured ply (for most beginners) and it would also be quite a big job to convert tourtured ply plans to the stitch and glue plans, since that method does not lend itself to a nice round hull bottom. However, he did not rule out any stitch and glue type hulls. We would probably want to specify the mast/sail set up to keep it as a one-design type boat. BTW, this is exactly how the Opti started. The "Optimist", a charity group from the Tampa area, had a contest to design a small sailboat out of a single sheet of 4x8 plywood. Perhaps the F12 could be the "New Opti"?

Maybe out of 3 sheets of 4x8 ply?

Like this Tim?

John,

Correct me if I am wrong but the designs that you and Wouter are presenting are still a tortured ply design, i.e. the side panels have curvature in more than one direction and so the ply sheet still has to be tortured i.e. bent in two directions at the same time. Although by keeping the amount of curvature in one of the directions small you are making the torturing process easier.

I don't think there is any way around this to produce the kind of hull shapes (which I think are good) that you are proposing

Does the software that either of you are using have the facility to produce flat panel patterns for the side panels that you are designing?

Gareth

You realise that the hull shapes and sizes that you are proposing are quite similar to those of the international moth. 3.35 length 2.25 beam with a planing bottom. It may be worth looking to some of their construction techniques.

http://www.moth.asn.au/building_registration.html
and

http://www.moth.asn.au/download/building_ply_skiff_moth.pdf

Gareth

Jalani, yes, that's probably more safe for the kiddies, and anyone near them! <img src="http://www.catsailor.com/forums/images/graemlins/shocked.gif" alt="" /> (I have 4 kids, I can tell you they can hurt each other and you, even with a baskettball!)

My designs are definately not "tortured ply", but I'm afraid to say that those of John are.

My designs ONLY bend the plates in one direction and therefor do not require any torturing. And therefor it is of course understood that my hulls will look a little more crude as a result.

Able to make the hulls out of flat panels bend only in one plane was one of the very first design criteria on my list.

Maybe later we may be able to twist the panels a little bit by making use of the natural flexibility of the panels but we'll develop that after have gained experience by building a few prototypes. Calculating the panel shapes is a whole lot more difficult when twisting the panels.





Yes.


Tim, I would like to have a wave-piercer bow, but the hull shape I'm working on now (simpler) has a straight bow.

The deck of my hull design arcs down towards the stern and bow. So that is also a difference with the picture made by John.


Wouter

I always thought it would be fun to connect two of those foiling moths with carbon cross beams, create a foiling cat!

Hi All

Firstly, I found over here that companies aren't too keen on shipping the ply sheets scarfed but unjoined, they don't like the risk of damage to the scarf during transport, and having to replace it.

Second, I can't remember, I'll get back to you. <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

Regards

Hi All

Now I remember, I was thinking the other night about wave piercer type bows, I wondered if it would be good idea or not, because if one were to include WP bows in their design that was for junior use (I realise other age groups might use them as well) but, having the most forward surface of the bow at basically waterline, there would be a greater chance of damage to others, as opposed to having the foremost part of the bow at the gunwale. I'm sure we probably had our share of mishaps or near misses when we were young, and probably still have them now.

I wouldn't dismiss the idea, but just a thought.

Regards

Hopefully I will have posted an old picture of an Impara Cadet, this would have to have been around 20 years ago. I haven't been able to get to the club to take any photos showing the hull shape bit better. It is very similiar to the Arafura in its rig, however the hulls are rounded tortured ply. Not quite a small mossie, but good little boat just the same.

Regards

Another good reason to pursue this design <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

At the moment I can't see how you are doing this then, the two plots you have presented so far seem to show a near vertical bow combined with non vertical side walls. I know you haven't finished yet but I don't yet see how you can have those two features without a small amount of torturing.

A small amount of torturing is not a bad thing it just makes getting the flat patterns more difficult.

I am keen to see how your design progresses, good luck.

Gareth

I can't see the problem with a small amount of stressing the ply. In fact, I would say it is highly desirable since it induces more stiffness to the design than would otherwise be present plus it looks better! Also, Wouter, I have to agree with Gareth - the sketch you provided indicates some bending of the ply in two directions. I don't see how it could otherwise be made.

The amount of twist is VERY small and developing the shape is very easy indeed. I'm going to make a stiff card model of my second sketch (as amended for Timbo) and see how it works out.

I agree, can freeship, calculate the panel shapes once you introduce twist?

Folks,
I'm surprised at the number of posts that are being entered on this. Just a couple of responses below:-

Phill eluded to a homebuild ply box and rudder here somewhere?

John,
I did and it is dead easy. You could be building the rudder setup while waiting for resin to cure
on the hulls. Just takes a bit of planning. The ply rudder setup will be a fraction of the weight
of a rudder system from a H14 and probably better all round.

How easy or hard this project is to complete in a short time span while not compromising on the final product will get down to well thought out building instructions. These can't be written up in detail until the design is finalised.

*************
"Of course you can have them make the scarf but not glue it together yet."
Wouter, once the ply is tapered for the joint it is extremely prone to
damage even if it does not leave your workshop. There is no way I would ship it at this stage.
There are a number of different ways of tapering the ply for the scarf join.
However anyone not confident in any of these should just us a simple lap joint.

*********************



"I can't see the problem with a small amount of stressing the ply.
In fact, I would say it is highly desirable since it induces more stiffness to the
design than would otherwise be present plus it looks better! "

Janali,
I agree with you on this. Apart from stronger and stiffer the hull will give the appearance of being fairer as well.
********

Regards,
Phill

Just thought I'd look at the drag for the different hull shapes.




Hull1 is a conventinal "blade" design, hull2 is a moth planing bottom design similar to what Wouter and John are proposing, hull3 is a Gcat type Deep V design. All hulls are 12ft long and are displacing 120kg. The slimmer Gcat hull has the lowest drag, but there is not a great deal in it.

With regards to hull 2 this program does not predict planing so if the F12 will plane at higher speeds then there could still be a benifit in going that route.

Gareth

Gareth,

All my designs up till are made with panels that only bend in one direction. All the rest is optical illusion which I'm actually applying to make the hulls look nice !

See here :



Also my bottom panels are significantly more flat then those shown earlier in Johns picture. Afterall I'm trying to achieve some planing properties with this boat. This version has straight sides and a straight bow. The one with the wave-piercer bow is the same but with slightly inward canted sides. The amont of side canting needed for swept back bow is so small that we probably can get that by just twisting the ply inward at the bow.

Work is continuing.


John,



How or where do you see it ?


Gareth,

Can you alter the box hull shape in your drag simulation to have 25 degrees keel panel angle. Meaning each panel moves up from the keel line at 25 degrees ? That is a promising hullshape and it will resemble the red hull much closer in shape and I hope in drag so too. while still presenting a relatively flat keel that hopefully allows some planing. Not full planing but just a little amount so that 2 or 3 knots can be added to the top speed.


Thanks you all it really helps when other people do portions of the work.

Wouter

From the cheap seats.



I'd strongly suggest keeping with the wave piercing bow to give this boat as much a modern look (within homebuild reason) as possible,
or as Phill said, "It will look like a bicycle with training wheels".
And also per Phill, if it's deemed an issue add a layer of glass

Looking at the sketch you provided:



Where the panels join at the bow and along the chine each side, there is undoubtedly twisting of the panel(s). The same could be at the stern but it is difficult to tell from a sketch like this.

The sketch is exacerrated at the stern to show the make up but truly all panels are flat in the real life application with the exception of being bend in one plane.

If you bend two non parrellel panels in their own planes and have them intersect with eachother then the resulting intersection line (the chine) will be curved in two planes. Because this line HAS to lay in both planes ! But each plane itself is still only bend in one plane and therefor not stressed into to compound curve (? right word for it ?)

Do this mind experiement.

Use a flat plat to make yourself a cone. Cut the of at a right angle so the cone is like a round pyramid shape. Now intersect the cone s little below the top with a flat surface. You end up with a circle as a crossectional shape. Now bend this top plate and again make its intersection with the cone. Now the crosssection will be an round but irregular shape. It will not be an ellips although it will appear to be one. No just rotate the top plate. The crossection and chine will be curved and angles in more then one direction but the shape and chine are still the result of only two flat panels bend in only one plane.

My point ? It is extremely hard to tell from chines or crossectional shape whether a shape is made out of the intersection of flat plates bend in only one direction or by stressed plates bend in more then one direction.

Wouter

If it's a boat for kids it needs to look like a boat for kids. There is a reason why things look like they're made for kids when, in fact, they are. An opti doesn't exactly look like a modern high performance speedster.

This is, of course, if you aren't expecting to market the boat to adults unless you expect to first sell to the adult in order to get them to build it for the kid, and then you've created the same circle we're in now.

65 kg (143 lbs) crew is a rather developed "kid", maybe claasified as a young adult? The boat can also appeal to an adult. Could also be two 32.5 kg kids, or there abouts.

Paint scheme can make the kiddy look. Looking at the photos of the Cadet's, some looked like Dad trying to make a "proper" boat and then there was this one Demon

true...
One could just get brett to build lots more hulls...

Another 12 footer that could be reconditioned is the kittycat..

Another idea non flexable pvc tube... Such as used in electrical cabling..
Its cheap...

The design stuff coming from the group of guys working on it is impressive. (I'm learning a lot)
I'm concerned that you haven't identified the:
What
Why
How
and When
very clearly yet.
Your doing well with the How , but the what and why has been
skimmed over. (IMO)

There is nothing more difficult than designing something simple.
I know it's in design stage but there has been discussion about differant rudder assemblies, differant size sails,larger hulls for bigger guys and I think the word carbon was even used.
This sounds like a broad based formula that may not fit into the What .(your really trying to do)

Are you trying to prove you can design a new simple boat or increase the number of youth sailors? ? ?

I know from doing a lot of project management that keeping a group of engineers on point can be like hearding cats.
I get the feeling that Flatlander(John) the customer in my mind and Wouter, the engineer are not on the same page.

We really don't need a 10 boat world wide F12 class.
It also seems there is a lot more interest from abroad than in the USA.

Just my opionions and observations, Nothing personal.

As for the why, you might need to read back to the beginning of this thread.... But most people posting in this thread see a need for something that is different from what is being offered for sale as a way of enabling youth participation.

I for one, as an American, have been looking for something like this for awhile in the interest of enabling youth participation. I believe the ability to home build it as very important because:

1) I think you can come up with a better boat for the purpose.
2) the creation of the boat between the parents/clubs and young sailors will help get them into it.
3) It does not have to economically viable for a company to produce it.

The last part is the important part - this means the design can live on, and people can have one or many in the future long after any company may have given up trying to make a profit and killed it. And, if there are only 10 boats in the world so what. Hopefully those 10 boats are being put to good use - maybe they exist only in one club, but then I'd say the mission is still accomplished. If at some point in the future another club builds 10 more, and then it takes off in a region, well, who knows. If it never becomes a racing class but a handful of families build them for their kids, mission is still accomplished.

Point is, I don't see that happening with any of the current boats available from a manufacturer, new or used, at least for the racing part. This has been an interesting exercise if for no other reason than some of us have been exposed to small buildable cat classes we didn't even know existed. If this fails, I've seen enough that I would try one of those designs for a youth program.

Agree on the need to keep it simple and reduce the exotic materials as much as possible. But, in some cases it might make things easier and cheaper, so the use/elimination should be considered wisely.

For the general thread:
On the needs to look like a toy thing - I think this goes both ways. You may want a toy look for the really young, but once other boats start to look "hot" the toy look will work against you. I agree with the idea that the paint job can suffice for the toy look for the young. Go for a platform that looks good as racey boat, not a toy. Apply paint schemes to make it enticing to the Spongebob set.

On sails - I believe something like this can be done such that a simpler smaller rig goes for the younger kids, and for the older kids a more powerful and interesting rig to keep them going. The same platform should suffice for both.

On the bows - the overriding factor here should be what is considered safer for the purpose of the boats - kids. If parents think that a potentially higher speed boat with a pointy end might endanger children who haven't learned the finer points of boat control, well, adoption of the boat may suffer. Those of us who have put kids into sailing programs can enlighten us as to what the prevailing mind sets are...

Just my thoughts...

If you build it they will come. <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />

Seriously, my nephew-in-law races Highlanders and has several grand-children getting up towards first sailing lesson age. I'm definitely going to keep him abreast of this as it evolves. To me, it would be a great to have something like this if you have young ones you want to get into the sailing.

I'm structuring the project as we speak as I too felt like the project was potentially going off in too many direction.

The vision I have for this F12 is as such :

First your points :

What ?

A good looking sailboat for lightweight crews 45 - 75 kg (optimized for 65 kg) that has its main focus on being really easy and quick to rig and de-rig (incl. transport) for a budget of at max 3000 US$ but preferably less. (Vanguard optimist is 2550 USD)

Within these limits, I'm trying to get maximal performance out of the design and it looks like that is developping rather well.

NOTE : IT IS NOT A PURE KIDDIES BOAT ! More on this later.


====

Why ?

So responsible older children, teenagers and the smaller adults can sail a high performance sail boat that is really fun to sail in these "instant thrill seeking / no hassle" times but that can also be a ladder to truly performant boats like the A-cat's, F16's, F18's, and Tornado's although the last is not a major consideration in itself. With this I want to have a good tool to build up a more young participation in sailing and get kids aways from TV's, computers and obesity by showing that actually doing something in real life is more fun then simulating such a life by a computer game or TV.

The second reason is to give active adult sailors like myself an enjoyable sailboat for the little hours of free time that are too small to rig our normal boats. Like evenings or the two hours before wife wants to go to your in-laws.

The real youngsters are best served by something like an optimist.

====

How ?

But combining all the smart idea's found on other sailcraft (like landyachts and skiffs) to cut down on complexity and cost while keeping impressive performance.

Sadly this is something no builder like Hobie or nacra is doing. They pretty much only scale down a large racing beach cat to 14 or 12 feet and make it out of rubber. That is neither inexpensive, not simple or performant.

But also by having a design of which by far most items can be home-build. This will cut down on operating cost but also will be another life experience for those who decide to go down this route. For several of us like myself it means we can have such a small boat on the side very cheaply by using components of our larger cats. This requires a formula setup.

Also the formula setup allows these adults to make a hull that will carry their weight reasonably well without having the lightweight crews forced to sail hulls that bounce over the water with each wave. Therefor different hulls for different crews => formula setup. will equalize racing between these crew better as well.


===

and When

That is a good question.

I've just come to the realisation that while I personally have the capacity to do jobs with respect to developping this F12 I don't have the time to do it nor the resources to make this a proper launch. Afterall I still have responsibilities in other area's. And because this design needs all the smart stuff of other design/boats it is pretty much a fundamental conflict if one or two persons need to investigate and cover all things.

I want this design to be prototyped this summer at the latest and have 90 % of the development completed by summer 2008 when the final FORMULA class rules will have to be fixed. And at that time I want a serious launch of the class, but those are details I'l cover later. There is absolutely no way 1 or 2 persons can do this. So we need all interested persons to contribute what they can. Often not so much in hard core design work but in making 3D technical drawings, testting setups, gethering info on materials and availability in local area's. And I'm begging for a person to build us a website and a wiki. Alot of it is fun stuff, the truly boring math and such can be done by myself and another person.

Large parts of the design are already in such a state that imaging, testing and develloping can start.

So "when ?" Is now

"When finished ?" dependent on the help we get.



I'm working out a document detailing this all tonigh and will post it so you can all read it and comment on it.

Wouter

Wouter,

a protest on the "The real youngsters are best served by something like an optimist.".
The Optimist is too hard to handle for the real youngsters alone. They would be much happier with a friend (or friend to be) to share the experience. A boat with more directional stability would make things a lot easier during launch. This is the experience from watching our clubs Optimist program.

Pat,


Hey, I'm not complaining. Going back to my first post in the Youth thread asking "May we spend some time talking about developing this?" above the image of the F12 concept, to where this is at right now? Wow!
And my nature is, with some engineering background, to think out loud and ask questions. And in that regard this forum is awesome in affording everyone from around the world to throw in their tidbit for concideration.

On the what, why and other than that, what Keith said. <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />

This has been said a few times.
Aside from Field of Dreams, I would like to know when it really worked.
I don't ask the questions because I don't want it to work, I ask because I would like it to work.

Our Fleet is arguably the most successful in the country.
We were told that our little Oneida Lake could never handle a National event. We have had many since then along with the largest Cat race in the country last year.

I say this because we also have the resources (People, Facilities, and Know how) to build a lot of these things in a hurry if it makes sense. I have been on the can-do side of things every time. I could probably build most of it with what's in my garage.

The questions still need to be asked.( I have read every post and have learned a lot)
Is having 10 boats really a success. Not to me, especially if their being built by sailors for kids that are sailors already.
We need a bigger pie.

Some of the greatest products ever designed never took off while marginal ones flourished and made people very wealthy.
Why? Sales and Marketing (You really need to look at Hobie here, if not, you haven't really done your How homework).
Good product, Sales and Marketing. Results don't lie.
There must be Design, Ability to Produce, Marketing and ultimately Sales(in this case building and the use of the boat by NEW sailors).

Remember: This all started with "Youth recreation trend"
and how to get more NEW youth sailing.
It's hard to stay on point.

This is at the brain storm phase and I would suggest going back to the What, Why, How on a regular basis to see if your doing what you set out to do.

Wordy disclaimer here

Formula 16 and a score of other Australian cat designs.

The moth class has largely been a homebuilders class for decades.

Weren't a lot of tornado's build in ply back in the days.

How did the optimist start ? TIMBER !


I can tell you right now that more of these timbers boats were homebuild then Hobie ever sells in the way of rotomoulded products. The mosquito design alone (now part of F16) was homebuild a couple of thousant times.

And there were more F16's in the last (200 boat) cat event that I went to then Hobie 16's

Now can we PLEASE get of the "HOBIE" bandwagon ? It is like a persistant and gusty crosswind when driving on the freeway of thought.

Besides I think that I can claim some promo and sales skills. That Hobie wave (and let alone the hobie twixxy tuddler doddly humpy dumpy and whatever name they think of next.) is still waaaaaaay behind world status with respect to the F16's.

Now I REALLY don't want to discuss F16's or "I did this ..." or "they didn't do that ..."

So lets leave "Hobie" out of the discussion please and focus fully on the F12 and just MAKE it work.




Sooo, who I volunteering for some work ?

Pbisesi ? Can we invite you to do some analysis work on how such a boat can be build by a group of amateurs at a sail club. This mostly with respect to hulls and sails the other points have al pretty much been covered. What would be too hard for such a group, space confinements, available tooling etc.

Wouter

Noted Rolf,

Thanks.

LOL! Now that's poetic! <img src="http://www.catsailor.com/forums/images/graemlins/laugh.gif" alt="" />

I think you missed the point.
Replace Hobie with Coke, Pepsi, Kleenex, Band Aid etc..

Refusing to at least recognize the success of what Hobie(or any brand above) has done regardless of how you feel about the company, product or the class association is missing an opportunity to learn things that could help you.
Success leaves clues.

Yes, I'm missing something. What are you suggesting, look for a Coleman Industries to market and back it? Is what is happening here going on in the wrong way? Should someone walk into XYZ corporation with conceptual drawings, a sales pitch and a "trust me"?

Analogy to the music industry, no big labels will spend any money in developing new talent. Why? They can let the crillions of micro labels develop them and attempt to sign proven, successful acts with no development cost to them.

Opposed to 30 years ago, it seems the same applies here. Mr. Alter had an idea and then he built it, right? And you can say the rest is history, which leads us to today. Is this "concept" earth shattering? No. Is it drawing some interest? Yes. Will it be successful, on the level of the H14/H16? Who knows.

Thank you for all the efforts ladies and gentlemen and pardon my ignorance.

Pat's simply saying that if you guys want to achieve a goal, figure out what goal it is because you're all over the place. I didn't read one line of Hobie-centrism in any of Pat's posts - only advise that's used in the majority of any kind of product development. If you guys are just having fun coming up with something, that's one thing...but this project was started under the premise that youth sailing on catamarans, particularly outside of the tight-knit sailing community, is largely non-existent and you wanted to do something about it. HOW are you doing something about it? HOW does this boat apply? HOW should it be designed to meet that goal? so on and so forth. Without some sort of unanimous direction this will end up with a 10 boat rotting fleet...not that there's anything wrong with that if that is all you are after.

John
What I mean is that people have to spread the word outside the current sailing community.
Hobie took off in large part from the Life magazine article and Hollywood movie placements. Bo Derek and such.
(Deep breath Wout, trying to learn here)
Having all this information here or even on it's own website is not nearly enough.
Someone like you will have to go to a local venue such as a yacht club or even a town or state park and pitch the idea to have a sailing program for kids.
You will need a team of people to build maybe 6 boats.
There would need to be some advertising in newsletters, websites and local papers that there is a sailing program available for kids.
Our town holds Parks and Rec for the kids in the summer for a small fee.
These are a bunch of kids that have no idea about sailing that could be introduced and hooked. You could then let the parents know that the plans for the boats are available and maybe have a how to work shop for dads that may have all the tools and ability already to build a boat for his kid that has never turned on a computer.
There are some sail schools at lakes near us, but they are expensive and only known to club members.
Design and building is the easy part. Manpower and marketing to make it successful will be difficult.

PS: Jake got the point

Wouter: How about a break down of the 200 boats and how you did.
Do you have home build numbers vs. factory boats that can be confirmed? That would be interesting.

If you see an issue that isn't getting the attention it should then join the group and work it out.

Currently, all you guys are doing is giving "DUH-advice" to others who are doing actual design work.

Pardon my French here, but there are a few "somebodies" involved with this F12 project. Several of us have pretty significant cat projects under our belts. And while we would welcome any help from you in actual design or analysis work, we will welcome it even more if you guys quit dispensing any more "advice" that our own 90 year old and fence sitting grandfathers would come up with.

Wouter

And yet the simple question about "what is this project targeting?" goes unanswered and the name calling and insults have begun. To answer the first sentence of your post, I think this question is a big issue that is not being addressed - so it was raised. I missed the part about official group membership though. If you can't handle public comments, you might reconsider doing this in a public forum.

Would you listen to the advice your 90 year old grandfather would give you?

SHITE !! I just realised, I AM MY 90 YEAR OLD GRAND FATHER.

Jake,




How about look 13 posts up and see your question anwered.

I'm truly sorry that in this storm of discussion and design work I've only been able to publically log 2/3's of all content. This thread is only 7 days old already I have over 100 pages of information, drag plots, hull shapes, bouyancy calcs when hit bu a gust and what not.

We are in the design phase right now because it is pointless to go up to a local authority with only a sales pitch but no substance. Not because we don't understand how this works.

Other boats at this time are waaay to expensive to build a youth program on. The boats that are inexpensive enough like the optimist are not that well suited to this role according to comments by for example Rolf and Phill who run youth programs in their area. Before you start on a job you look for the right tool to use. F12 is the tool that many of us have felt missing for a long time.

Are we wrong in this assessment ? We can be, but you guys are just kicking in open doors.

You are not telling us anything we don't know already or know to be false. Nobody is helped by that. As and you guys don't appear to be doing any of this yourselfs, can we then ask that you don't frustrate this effort. For nobody can predict whether this will eventuall work or don't work. But anyone can predict with absolute certainty that it won't work if you are succesful in derailing it.

Hell, if I had a dollar for each time I was told that F16 would never work ..... !


Wouter

Hi All

Have to say, I agree with Wouter <img src="http://www.catsailor.com/forums/images/graemlins/shocked.gif" alt="" />, its not as though theres 50 of these boats being built to 'rot' away in backyards if it doesn't take off, not saying that necessarily happens if a class doesn't become a 100 boat class.

I would much rather go outside build an idea to see if it works or not, rather than putting it all on paper and telling everyone it does. This planning stage and the building of one or two or three boats, needs to happen.

Everyones got their own ideas on how this cat should or could be built and rigged, but the fact remains you need to build one and try it, if it doesn't meet the ease of build, ease of sailing, ease of transport, or some sort of problem becomes evident, it can be altered to bring it into line, without having to bring 6 or 10 or 20 of them in line.

I've made myself 3 stainless mast bases for my boat over probably a 3 week period, to fine tune its design, so when I do fix it to the mast, I don't have to remove it and start again after one sail.

Now, please, we all know how hard it is for me to agree with Wouter, lets not make a habit of it <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" /> <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />
(take that with humour please Wouter)

Regards

This is a worthy “project”, and to me illustrates, more than anything else, a cumulative vocalised realisation by more people than I have seen in the past, willing to focus on the fundamental problem in cat sailing over the last thirty years, that youth numbers sailing cats have been reducing at an alarming rate. To the point that at the moment it is very difficult to see any cat being sailed by anyone under the age of 40 in the foreseeable future. There have been many “reasons” enunciated as to why this has, is, and probably will continue to occur in the future, but none of these “reasons” have really helped to reverse this trend in a practical sense.
What we are seeing here is, at least a positive attempt to offer up a real practical alternative. There are a lot of varying “points of view” as to exactly how to proceed, but proceed you must. If any (or many) designs are developed from out of this discussion, (and not just further discussion), then there is the possibility of success. The first step is to design and build a cat, iron out any eccentricities, whether they are in the construction, the material supply, the building techniques, the cost, or the sailing characteristics, and then, when it is ready. And only when it is ready, present it to its potential market.
If ALL future difficulties that MAY arise with marketing, promotion and publicity, mass manufacture, export, and all the other myriad of problems that exist within the commercial world that are involved in operation a successful business were brought into consideration and applied at the planning stage of any actual embryonic project (like this one), then I don’t think any idea would ever “get off the ground”, it would all seem to be “just to hard”. So put simply, first steps first and don’t worry about that second step until the first is finished (or else you could stumble on the first)

too much popcorn - and you will look like Robi's avatar (he he he)

From what I've seen there is no doubt the boat can be built.
Doesn't seem that difficult.
I was simply trying to talk about what is ahead if it is to be a success and do what it was designed to do.
That is to promote youth sailing as I see it.(or is it for designers to impress themselves?)
To say you couldn't start talking to people right now about running a youth sailing program is just wrong.
Worst case you could use old $1000 or donated boats.
They could even be Hobies. (God Forbid)

Hi Pat

Well the way I see it, and I'm not being disrespectful in anyway, thats probably worthy of another thread, Youth Sailing Programs or Youth Marketing. I do see totally were your coming from, let that be clear. But I started this thread as to not get into the nitty gritty of promotion, or programs, cause thats where the other thread was heading. Its more so designs could be looked at, discussed and ideas floated as to the designs.

Regards

Well...I've been away for the past few hours setting up our Hobie Fleet 297 display at the Kansas City Boat Show (Bartle Exposition Hall, Booth 212, Wed thru Sun, stop by and say hello!). Have to run now for the Building Committee meeting on the new Sailing Center...starts at 8:30.

Maybe later I'll have time to oil up the jig saw and tidy up the garage.

When we have a boat built we'll start talking.

F12 enthousiasts,

At the following link I have placed a document that is intended to set the first steps in getting this design project structured properly.

www.xs4all.nl/~whijink/formula_12/The_Formula_12_sailboat_project.doc

It is a word 97 file.

This 280 post breanstorm session we had over the last 7 days was both inspiring and overwhelming. But the time has come to make sure that the efforts of one volunteer build on those of another and that with each step we get closer to completing the design and building of a prototype.

I'm back at work so I too will have to work alot more efficiently then I have done of the last couple of days.

On the work done already I say that this project has a really promising outlook. Sure we'll encounter some setbacks and hick-ups along the way but the numbers have already shown that this basic F12 setup has ample merit. To name one example. Performance approaching that of the H16 is expected and that is really fast for a 12 foot design. Also the goal of 3000 US$ or less seems very reasonable even with bought rudders and such.

So I propose to start implementing the steps described in the document and get this project under way properly so mangan can build our prototype !

Who is with me !?



Wouter

How about something along the lines of what the Soapbox derby has done in the past for gravity car racing (young teens in the US)?

Set up your formula format, offer scholarship prizes at local/regional/national/international levels (the higher the level, the greater the amount of the scholarship/savings bonds for educational use). By offering educational scholarships, the parent would have a “justification” to spend money on the project “it’s not frivolous waste of money…it for their education”, that coupled with the opportunity to make life long memories, teaching young teens how to work with tools, and share their love for sailing all accomplished at the same time.

The design can be tweaked to anything within the box rules, allowing for freedom of individual expression (just like the soap box derb, where people don’t complain about everyone not racing the exact same car).

The stock base plan you are working on could be offered for those who are not interested in “designing their own” but want to build, or used as a starting place to make modifications. Building "work shops" could be held on weekends to help children/parents who do not have wood working/fiberglass skills, given by volunteers who would like to share their boat building skills with the next generation

The rig could be offered for sale by the governing body just as the axles and wheels are for the cars. The youth get a local business to sponsor them by providing the funds to purchase the rig at cost from the governing body. By taking the expense of the rig out of the equation, the overall cost is substantially reduced, attracting more sponsors than if they had to absorb the cost of a whole boat.

Finding sponsors to fund the soap box cars is not a big problem.
A parent owned business, or employer is frequently the source. Many businesses would love to have their company name on the side of a cat, photos of them splashed in the sports section of the Sunday paper, the sponsors can pay for it out of there advertising budget..

A win for the child…he/she gets to learn how to build something with his/her hands, an opportunity to see it all come together from design to completion…experience not only sailing…but sailing on a boat they created. A win for the Dad/Mom who get to spend intimate time with their son or daughter, working on a project together and forming priceless memories while being able to pass on their love for sailing. A win for the local sponsors as they get to help a child develop character, and be a advertising partner in a unique opportunity that could ultimately expose his/her business to local/regional/national/global markets. A win for sailing as it has the potential to introduce a whole new generation to catamaran sailing.

A Win/Win/Win/Win situation...what more could you want?

This is just one answer of “How” it could be done.

Regards,
Bob

Hi Wouter

Just to clarify, the proposed class rules in the document are the ones the prototypes are to comply with, or are they just proposed class rules that could be introduced or voted on in the future?

I just think a couple of the rules restrict development in a developmental class. I don't think any rules should be settled on even as proposed rules until some further discussion or ballot takes place. I've spoken to several sailors over here (Oztralia), some involved with the forum and some not, but we seem to have some different ideas, most which have floated on the forum already.

Apart from that it all looks pretty good.

I don't know if means much but as far as I'm concerned, you'd be the man for the project manager, so I guess I second that. But you will have to answer to the board of directors <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" /> <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" /> <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

Anyway let the games begin....or continue <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />

Regards

Reading through Wouters document with an emphasis on safety, has just reminded that this boat is not going to lie on its side if it capsizes, it is almost certainly going to turn turtle straight away with the short mast setup, so you are probably going to need make provision for a mast head float.

Gareth

Having looked at the windsurfing rig and giving it a thumbs up have you considered using windsurfing race dagger boards for rudders, I've been sort of looking at them for my F16 as the trend is getting smaller and smaller surface areas as per the A class, the couple of old ones I have from older windsurf boards ( given to me from a local windsurf school ) are not quite big enough for the F16 but a smaller rigged 12ft'er, now that maybe a possibility + there are loads of these just laying around.

Gareth,
This really gets us back to who is the target market for the boat.
If it is children 7 to 12 yrs that weigh less than 60kg then having the boat invert could be a good thing.
An inverted boat does not drift anywhere near as quick as a boat on its side. They could catch up with an inverted boat but never catch a boat on its side.
Very young children are unlikely to be able to right the boat and the inverted boat provides a safe area between the hulls where the children can wait in for assistance.

Regards,
Phill

Phill, now you are taking all the fun out of it for the kids. The thing they most like to do is capsize the boat. If they aren't going to be able to right it again by themselves, what is the fun in that?

Had an hour or so to play with my design last night. This is the Mk2 version:

Good point Phill,

Mary, its swings and roundabouts, a cat is the best diving platform in the world so they might be willing to trade being able to right the boat. Many kids might find an inverted cat more fun than one the right way up <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

To my mind the main advantage of an F12 for young children is stability not performance.

Gareth

If we take the Laser Funboat as an example (much as I hate the damn things) - all the kids we teach, seem to prefer turtling them and then 'bombing' each other from the upturned hull. With such a small rig they're also an absolute doddle to right from turtle.

I have to say I can't blame the kids as those boats make better platforms than sailing boats for teaching purposes. Our real teaching is now in Toppers.

I don't think so, Grob. Better to have the masthead float. Do you want a child to get trapped underneath a turtled boat?

After all, if this is used for kids, it is probably going to be in an organized program, because it would be necessary to have a chase boat to keep them out of trouble. It's not like you can take it to the beach and shove your kids off and wave goodbye.

Why is that? what is going to make an F12 different, so we don't fall into the same trap?

Gareth

Have you seen a Funboat?

Dinky little skegs on rounded hulls that weigh about 100Kgs. Single rudder and a rig set well forward that doesn't have enough power (or shape) to drive the thing upwind at a proper angle. The kids end up reaching everywhere and invariably have to gybe round to change direction because, unless you REALLY know what you are doing, it's almost impossible to tack.

This is something we really need to avoid, I think that the F12 has to be very manouverable, (another thing that I beleive is more important than speed). I am little concerned that with the current hull shape and no boards we may be falling into the same trap.

Gareth

I'm not sure why you took all this to be so negative, I never said anything derogatory about the design, never said you guys don't know what you're doing (designing a boat), and never said "it won't work". think it's an interesting project, but one that (currently) doesn't have an implementation plan or a clearly defined customer. I know it's a home built designed for fathers & mothers to build for their kids and that several of you here are chomping at the bit to build. However in order to do genuine marketability and feasibility assessments, it needs to go further than that customer base and will likely be different between local regions. If Joe Blow (who knew little about sailing) decided he was going to build his son a boat, there are a lot of other options out there. Obviously, the general consensus here is not interested in this line of thought at this time so I'll let it be.

Valid points Jake, and work to be done if this project is really going to get anywhere. I was under the impression though that this is 'a good idea' that might go somewhere once a few are built. You know, sort of self energising. If this is going to be a structured effort to start an introductory youth class then we need more expertise and effort than is currently being displayed in this thread.

I for one, will be going my own sweet way and, when time allows, build my own design of F12 for my 13 yr old son to sail. He's currently in the RYA Topper squad but is proving too light for a Topper once the breeze gets above 10mph. An F12 could be the answer. Light, fast and cheap.

There will be at least two in the UK then, as I will build one for my kids.

Gareth

Ahh...Worthy of discussion as F12: Promotion of a Product or F12: Marketing to the Masses?

Grass Roots method is all I can offer.

Personally, I'm not interested in marketting, not interested in implementation plans, or feasibility studies, etc...

I just want a set of plans for a small boat I can build in my half of the garage. If I can help serve others' goals with no skin off my back, I'm all for it.

I'm concerned about using windsurfer rigs/sails. The camber is built into a windsurfer sail when it is initially rigged. The only control a windsurfer has is basically the traveler. I don't think this will give suffiecient gust response especially for a kid.

I'm thinking a boomless rig like the Bravo or like the N6.0 may be the answer. You could even roll the sail around the mast to store it. You could also even shorten sail by reefing it around the mast.

Oh yeah, And I think a Hobie Bob type device would be a requirement. I know the kids around my lake like to go out and turn their lasers over all the time for fun.

Mike Hill
www.stlouiscats.com

Good luck expressing any concerns.
This has quickly turned into Wouter's pet project.
There have been a number of issues brought up that are quickly dismissed and the design pushes forward based on what Wouter wants to do.
After reading the word document I'm amazed at how information can be interpreted so differantly.
There have been close to 300 replys between the two threads.
There are a pretty equal number in favor and another group expressing concerns.
The paper says that without this boat that youth programs will be hard pressed to succeed.
It says that the five qualities, as seen by the self nominated project manager, are not met by any boat out there.
It also says the boat must be able to keep up with a Hobie 16. Why does that matter unless you have a personal agenda.

John's(flatlander) very well meaning and full of merit original post has turned into Wouter's personal ego trip.

If John, phill, matt or jalani want to push forward then they should.
They all seem resonable, probably actually have kids and understand the very real concerns should be considered.

Do we all want to read how Wouter is the father of the F12 forever as we do with the F16?

I thought we were an autonomous collective...

That's how I see it. Phill stated his plate is too full with summer and Blade responsibilties to pursue at this time. I'm really just an innocent bystander in all this and do appreciate Wouters effort. I can stand him taking credit (just add a grain of salt) for pushing this through, heading in a direction, consolidating information AND documenting it for more creative discussion. Otherwise it may have been a lost post.

If you go read the original F16 documents you'll see the same reference to a colaborative effort.

I'm guessing the H16 reference was influenced somewhat by my harping here, maybe faster than the rotomolded product available is a better way to state that.

Whatever your thoughts on Wouter and his agenda, he, and Phil are uniquely qualified to spearhead this IF you really are interested in the F12 becoming a reality. They have just walked this path with the F16, had to address many of the same questions expending much time and effort. The naysayers came out in droves claiming the F16 concept would never work (some are still trying to call it a “fad”)…well guess what? It’s working…slowly and surely gaining momentum.

Now the idea of a F12 is receiving attention and the need of a Project Manager is obvious… but how many have the time? …the contacts?... and the experience? to make it “happen”. How many who qualify have volunteered?

Its not that others couldn’t do the job, its just most would have to start from a blank screen. Wouter/Phil(with input from a host of others) already have the “F 16 model” honed over the last 5+ years…all they have to do is insert the F12 variables. If the goal is truly to benefit the kids, and get this thing off the ground as quickly and efficiently as possible, Wouter may be the best man for the job. Is it really important which ego gets credit if youth catamaran sailing is benefited? While this is a definite team effort, it is very advantageous to have people at the helm that have sailed these waters before.

“There have been a number of issues brought up that are quickly dismissed and the design pushes forward based on what Wouter wants to do.”

Many of these same issues were exhautivly considered and discussed to death when setting up the F 16 class…A good Project Manager has to be able to make decisions, even when they are unpopular with some on the team. As you know there is never going to be a point where everyone is 100% happy…that’s life.

At some point one has to decide whether this is just an intellectual exercise like most ideas on the internet, or push forward to make it reality.

Regards,
Bob

About the wood: I know some guys who have built the little Cape Cod Frosty boats. http://www.capecodfrosty.org They buy luan door skins and cover the bottoms with very light cloth, then epoxy. Not fiberglass cloth, just any colorful print and very light weight. The hull looks likes like a shrunken Opti and grown men race them in the winter...in New England! So my question is, do we really need to use expensive marine ply or can we get by using cheap off the shelf stuff from Home Depot, with lots of epoxy to stiffen it up? Or, is the marine ply essential for strength? BTW, most guys who build wooden Opti's use regular plywood, not marine ply.

The discussions I've seen regarding using Luan (door skin, or flooring underlayment) for small boat building is that a lot of people do it, and it works very well as long as it stays encapsulated. It doesn't last as long if it gets wet. It's well finished on both sides and relatively free of voids. Best use would be for a boat you're not going to put a lot of investment into. It may be a good choice for a boat like this, especially if the hulls are easy enough to build - if one goes bad because the encapsulation was compromised, simply build another.

Exterior grade ply would also work fine for most applications - the thing is to make sure the grade you are using has minimal voids in the middle layers. I believe A/C has less voids than A/A if I remember right. It certainly is used in a lot of applications for plank on frame. I might be leary of it for tortured ply designs, as any voids could cause problems with bending the sheets. The glue used in exterior is better than that used in the luan.

Mary,

My idea was to have a pocket in the head of the (squaretop) sail where on either side a sealed piece of plain styro foam can be placed. A 500x150x50 block on either side should be enough to provide 7.5 kg * 6 mtr counter leverage = 45 kgm. That would be the same as a 1.60 mtr tall 50 kg sailor hanging of the righting line.

And when done this way it will not look badly at all and it will be aerodynamic (end plate effect anyone ?) . Another ideas is to stuff the top of the mast and the sleeve of the mainsail with shaped (and sealed) styrofoam.

As styrofoam is commonly available for a few bucks you can just replace it now and then.

Wouter

Jake,

You willing to analyse and work out this branch of the F12 you feel is lacking attention ?

If so then I'll welcome your report and you can rest assured that it will looked at really hard.

If not then I'm afraid there are more pressing things to attend to at this time


Wouter

When talking about Luan and similar materials for boat construction, one has to consider the cost savings of the Luan over Marine Gaboon Plywood in contexts of the complete hull construction. It is easy to dismiss the true cost and say if it breaks I’ll just build another one…but let’s look a little closer.

You have the expense of:
1) Plywood
2) Stringers if any
3) Bulkheads
4) Epoxy resin for glue sealer and fairing
5) Fiberglass tape for Stitch and Glue
6) Cabosil for glue and glass bubbles for fairing.
7) Brushes for applying the fiberglass cloth
8) Sand paper
9) Primer & Paint
10) Gloves/mask


The labor of:
1) Laying out/cutting/fitting the plywood panels
2) Stitching the panels together
3) Applying the cloth tape
4) The fillets
5) Cutting/fitting/installing the stringer/bulkheads
6) Cutting/fitting/installing reinforcement for the beams
7) Cutting/fitting/installing the decks
8) Fairing the hull for paint
9) Priming/painting
10) Assembling the boat ready for use.

In the grand scheme of things, the cost of quality marine plywood (which is going to provide stronger, longer lasting, lighter, fairer hulls) is money well spent.
How much is your time worth?
How is the child going to feel when the boat they spent so much time and effort on starts falling apart because dad/mom saved a couple hundred bucks by using cheap plywood? Remember that kids tease unmercifully.
What are we teaching the kids when we take “short cuts”?
What are the chances they will want anything to do with making a replacement for that delaminated hull?
Never enough time or money to do it right the first time but always enough to do it a second time….?

My dad taught me…”Do it right or don’t do it at all”... it has served me well.

Regards,
Bob

The F12 will feature a different rig then the windsurf as standard. The windsurfer option is just an alternative to allow others get to the water at a minimum of expense or effort. It is up to them if they decide to go that way.




No full length battens means significantly less sail are (about 30 % less) and a sail shape that is very hard to control. Both of these translates directly in to a slow craft with ill mannered behaviour like difficulties tacking. A boom less rig has many disadvantages which all outweight being "hit" in the head by piece a 750 gram alu tubing. Additionally the bottom sailshape of the sail is crap in anything other then pure upwind work and such a boat will pretty much as bad as the laser funboat.

Again this is the laser/hobie way of doing things and we want a boat that is significantly better. Otherwise everybody go out and buy Funboats/Bravo's


Wouter

Pat,

Is it you that has a personal problem with me ?

Are you practically saying that I do the F12 so I can get back at the H16 ? When you wrote :





Additionally I truly am the father of the F12 design.

The drawing that started all this is mine. The concept design that was depicted was also mine. Phill came with the idea of doing a small catamaran but the basic setup was my reply to his request. This started a few years ago.

Halve the design was already finished before discussion even started on this forum as Phill and I had been working on it over the last few years in between other projects like the F16's and F18's. Some prototyping of hulls had already begun, as Phill mentioned in one of his own posts.

So even if I stop right now, I 'll still be the father of this design together with Phill. There is no way around that.

Maybe you should also consider the fact that many aspects of the design have already been investigated by Phill and myself in the past. That is why I can dismiss a good portion of the suggestions; we already know there is no merit in them.

Why is it that you don't want to make use of these experiences gained, it is only because I happen to be Wouter.

By God it seems like that.

Now this is my last reply to you, I'll ingore you from now on as clearly you have nothing valuable to contribute.

Wouter

Over time I'm came across many boat building pages on the net and a good portion of designers and builders seem to suggest that normal ply can be used succesfully if small defects are not magnified by having the material loaded up to its limit.

Personally my take on things is that if the F12 hulls are truly easy to buid then it may well be worth the risk to just use normal ply and see how it holds up. If it does crack or something then it can be repaired relatively easily and then the hull can be glasses over.

Once a hull is glassed over the inferiour aspects of normal ply should really not be a major issue in my perception. But it will be best to check with Phill on this matter. Afterall he has 25 years os experience in building these things.

Wouter

think if you are going to invest 100 hours in building a boat, the cost of okoume is not much. The other thing to consider is that it is about 10% lighter then luan and 30% lighter then douglas fir or baltic birch.
I have built small boats out of okoume, marine rated douglas fir and other stuff out of luan. Luan is way inferior in quality. The faces are very thin, the core is thick and has voids, it does not like compound bends at all.

Do not cheap out on the plywood.

I was looking at the design and I think if you are covering it with 6 oz fiberglass on the outside you can use 4 mm okoume for the hulls no problem 3 mm might be pushing it.

A 5 piece stitch and glue hull 12 ft long with scarfs, and no daggerboard trunks and with full sized templates I would guess you are looking at around 40 hours per completed hull. Add another 20 per hull if you are super anal about fairing it and painting it with awlgrip or similar.
Build the rudders out of 2 pieces of 1/2" baltic birch. Make a design and have someone cnc the shape, then glue 2 halves together, run full lenght Uni carbon down the middle of it on each side then glass on one layer of 6 oz cloth and fair it.

If you get someone to make the cores for the rudders, it should cost ~ 150$ for the cnc cutting. Everything else can be built.

Just my thoughts.

P.S. do a web search in multihulls world about 10 years ago a german guy wrote an about making a 14 ft cat that weighed ~100 lbs to sail in indonesia on vacation. He shipped the plywood precut and built it in 2 days in indonesia and sailed it around the islands for a few weeks. He used a windsurfer mast.

Cheers,
Eric

We'll let the jury decide.

I have a problem with how you treat people that are offering advice based on their experiences.

I have sailed every regatta and fleet race for the last three years with a crew under the age of 12.
That is something in the area of 250 individual races.
I have things to offer to the big picture you can't even begin to understand. I have tried to offer constructive input.
Phil and others have acted in a professional manner when questions were asked. I have no problem with him or the project.

As for the word Hobie. We might as well be ringing the bell for Pavlov's dog.

If you look back through this post you threw the first stones.

Everybody !

Posters like Eric Anderson with good info PLEASE take the time to type out your comments in a Word document and send it too me. Then I can post it on my website for all to read and improve access to data for everybody.

In the last 24 hours we have gone to 337 posts from 278 ; that is 59 posts in just under 24 hours.

I can't archieve that much info in a proper manner. Everything needs to have a context, source and listing of assumptions in order to make this stuff understandable say 2 or 3 months down the road. Alot of context is currently provided by the structure of this threading but that WILL be lost over time.

for an example look here :

www.xs4all.nl/~whijink/formula_12/F12_Crew_weight_analysis_vs_1_10012007_Wouter_Hijink.doc

If we are to make use of all your contributions (which I really do want) then you have to structure you contributions and supply then to the project in a well developped and standardized manner.

Otherwise the chance are that your comments will be lost. This is a huge pile of work that somebody (as in ME) has to work through next to me own design work.

Wouter

The given set of rules are just to give you an idea of what is going on. I think there are still to undevellopped to even use for actually building prototype. I've identified a few more loop holes that need to be close. Also the cube-square analysis provided some insights that need to be dealed with. We may have to lengthen the hulls from 3.65 to 3.90 mtr. That 4th power scaling factor that is very important from a dive resistance point of view is limiting our sailarea-mastheight combo to a rather slow boat. Lengthening the hull from 3.65 to 3.90 mtr makes a significant difference as the 4th power is such a stronger relationship. I'll try to write this out in a word document and publish it when I find the time.

Wouter

Wouter, I probably missed it in all this, but what is your web site address?

Wouter, do you think it would facilitate your project if there is a separate forum for the Formula 12? Rick is willing to create a forum for it, if you would like.
Let us know.

I would be very thankful if contributions beyond simple "Hey what if ..." are worked out using this template.

www.xs4all.nl/~whijink/formula_12/F12_Crew_weight_analysis_vs_1_10012007_Wouter_Hijink.doc

I used this template to formulize the first entry into this open source design.

I deals with the expected body mass and body lengths (latter being closely related to age) to get a feel for at which F12 crew weight range we have to design this F12.

The advantage of such formalized setup is that if somebody comes along and wants everything explained to him again we can just give him the link.

If he disagrees then he can work out a counter analysis and present that through the same channels. Then the two articles (viewpoints) can be maintained side by side and in time the better one will be incorporated into the design. This is the only way to keep this discussion somewhat under control.

Also Anybody having critique but not making any properly developped counter analyses can then be effectively "processed" and asked to stop wasting time of people who do actually research this stuff in a scientific manner.

I'm looking forward to your contributions.

And yes up till now it was easy, the hard work has just begun ! <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

Wouter


P.s. when you read the article, take a look at the table and see how the beginning of singlehanded sailing starts just when the doublehanded sailing becomes sluggish. In effect small kids start out doublehanding the boat and when they get too old and big to do so they are ready to start single handing. These two regimes seem to link up nicely.

Wouter

Making a more accessible webpage is somewhere on my to do list but that listing has gotten pretty long lately. I didn't quite expect the response when I first place the F12 picture in this posting :


http://www.catsailor.com/forums/sho...;Number=94107&page=&vc=1

In response to the questions asked by you Mary in the thread "The perfect world for beach cats? "





Yes,

Additionally I want to get these two discussion threads of the main page as they are now pushing all other postings off the first page. I don't think that to be a good thing for www.catsailor.com

Is it possible that Rick copies the two F12 threads and the one which you started to this new forum ? I really don't want to loose these threads in the 65.000 other posting in the mean forum ?

Thanks alot for your help.

Wouter

The threads on the open forum cannot be transferred. But for your own use all you have to do is put them in your "Favorite Topics," and you will have them saved forever and can access them easily. If you want to transfer some of your posts over to threads in the new forum, you would have to do that manually, with copy and paste.

As a gesture of good will I have reviewed all of your posts in the F12 threads and answered them again.

http://www.xs4all.nl/~whijink/formula_12/Pat.doc


I'm quite intrigued as to what things you can offer that defy my understanding. Your comment made me wonder if I had missed something, but I really haven't found anything in your posts that would come close to that. This is nothing personal but just a honest appreciation of the facts at hand.

So surprise me ! Or rather, surprise us all.

Wouter

Nice one! I'd like to build a small fleet. My kids will love this…<img src="http://www.catsailor.com/forums/images/graemlins/cool.gif" alt="" />

Wouter
Good will should be there from the begining.
I could offer that there are many many people out there that would be very valuable to this effort that will have nothing to do with based on how you act.
I base this statement on the variuos PM's, emails, phone calls and face to face meetings I've had with people over the last week.

When your truly good at anything, you don't have to tell anyone.
This isn't to say you don't have ability. What you do have will not be appreciated much until you learn to handle yourself in a professional manner.

I will stay out of this now.

Humpf, I haven't figured out how to link to a specific post <img src="http://www.catsailor.com/forums/images/graemlins/mad.gif" alt="" />

Right,

Well, nobody is stopping "your network" from succesfully inplementing a rival (youth) project totally unrelated to Wouter Hijink.

I'm sure there are other ways of getting things done then the Wouter method, but I can't transform myself into somebody other then Wouter. In turn your guys won't have anything to do with F12 and this will circle back onto itself for ever.

Effectively making this a "Could have, Would have, Should have" discussion.

In my experience these are not very helpful in getting things done.

As such your idea to end it is a good one.


Thanks for the parental advice about learning to behave myself in a professional manner.

Wouter

I wouldn't work for someone (i.e. for money) that treated people the way that you have so I have very little interest in volunteering for such abuse. So no, sorry, I'm not interested in assisting at this point.

I think this thread needs moving to the F12 forum !

Wouter…why so caustic? I thought you were the right man to head this thing but obviously I was wrong. Your talent and experience with the F16 has been overshadowed by your inability to communicate in a civil manner.

Contrary to your belief… you are not the first person to design or propose to build a 12 foot catamaran. When you go into the mine, mine, mine rant you sound like Al Gore when he was running around telling everyone he invented the internet. It’s ludicrous.

You have a lot to offer on the positive side of things, why do you feel the need to pick a fight with everyone you come into contact with? Why are you always so pissed off at the world?

Regards,
Bob

Well, maybe I'm just not such a nice guy ?

Over a beer and a bowl of peanuts I'm probably alright.

But when working to get results ... ?

To be honest, I don't know how else to get results.


Well, maybe it is wise to turn this whole thing around.

I propose that the group of persons having problems with me personally will find a new F12 project manager and the soon as he (or she) presents himself I will step aside and completely leave the project.

The new manager can then proceed to teach me and everybody else how to get results in a nice and civilized manner.

I'm really serious about it.

Lets give this a go.


Wouter

Why not let's put away the ego and get to work. ..... <img src="http://www.catsailor.com/forums/images/graemlins/cool.gif" alt="" />

Wouter,

While I don’t often participate in the discussions on CatSailor, I am an avid daily reader. I must tell you that I admire your drive, creativeness and passion for catamaran sailing. I enjoy reading your technical comments because they seem to me well thought out.

I also admire the way you have taken the initiative of this F12 project, because I know how difficult it is to lead a project. I started a business against great odds and against the advice of many nay-sayers, and I recall all the times that I had to stick to my vision and rely on my drive to get the job done. Even though I had many people working for me, I often found myself working long hours in isolation.

While initially this served me well, my business was only a marginal success, which frustrated me greatly. I couldn’t understand why so employees stood on the sidelines taking potshots with crazy ideas and didn’t get with the program to make the company suceed. Often I found their advice ill-informed, frustrating, and distracting and I began to question their motives. However, a close friend and confidant suggested to me that my actions discouraged my staff from participating and that ultimately my company would fail due to my actions (or in-action).

So, against my instincts, I started to listen and encourage dialogue. Often I had to fight back the temptation to lash out at ridiculous notions to keep the ideas coming. However, as the President, I got to choose to implement what made sense and what didn’t. When I held back my harsh criticism on the bad ideas and went out of my way to recognize and implement the good ones, I quickly found out that I was able to accomplish far more with the help of many than I ever could alone. Not surprising my business grew very quickly and profitably.

I don't know if there is a corollary here between my business and your F12 project, but my sense is that most people admire your work and want the project to succeed, and genuinely want to help, but are frustrated and concerned that your actions may impede the success of the F12 program.

While I wish I could provide the technical and logistical help you seek, I hope that sharing my personal experience will help your project succeed. Perhaps resisting the temptation to criticize may in the end get you the help that you’re looking for.

Good luck – I hope to be able to build an F12 for my 10 year old daughter next fall!

Willem Nieuwkerk

That was nicely put ! And even though we keep out heads down most of the time, I think that the majority of us feel the same way. Well done to everyone working on this project.

Now this is an excellent post.




Now this is exactly what it is.

With the possible exception that I do understand that this indeed happens and that I really don't really question their motives. But I also found that that really doesn't matter much because they still make ....

Maybe I even find that the most frustrating of all.

Also I wish people in general realized that there is a whole lot of work involved. And that after posting an good idea is takes many many many hours to design the idea into something that actually works. I found it frustrating to see the initial poster taking more credit for the end result then the guys who put all the hard work in. Smart idea's are very good but also only 5 % of the total project. Hence the "father F12" spin-off.

That is the problem of this situation with the F12 as seen from my viewpoint.

How to solve this ?

Your suggestions are pretty much the only available route aside from just developping this F12 with people who take the good with the bad and can work with me and hate me at the same time.

I think that I grew cynical over time with other projects. Not a good character feature, I admit, but also a really hard one to beat. Now I can do this F12 succesfully as project manager, but as it is a demanding and tedious job to be done in the little hours of the night after a tiring days work for no extra pay. So I fear I won't be really able to rise much to the desired level, that would take more energy then I'm able to give at this time.


Therefor again, I'm fully prepared to be replaced as project manager. I mean this very seriously.

I really won't hold it against anyone if they support the new guy. Hell, I really would love to sit back myself and make all kinds of (possibly ill-informed, frustrating, and distracting) suggestions to be worked out by other people and then still claim that my contributions were key developments. <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" /> (joke!)

If nobody does step up to the plate then maybe we all should just consider the words :

"You go to war with the army that you have, not with the one you want"

As in having an F12 but learning to forgive Wouter for being a ****, or not having an F12 at all.


Wouter

Well, if it would help you, we could eliminate this forum, I suppose, so you would be able to work in peace and solitude without outside influences and aggravations. But Rick won't have time to do that until next week when Tradewinds is out of the way. Let us know what you would like to do.

Wouter and all,

You Wouter, remind me of my father. He is very intelligent and has an inventive nature. Never spent a dime on anything he could do himself, even if it took him all day to do so, taking extensive research and building of jigs and tools to complete.

He also never understood why everyone else did not see things as he did. And this truly bothered him. His analytical mind could not fathom another human not processing things as he did. My nature is creative and I used to annoy him to no end by asking questions. ALWAYS, his immediate reponse was one of chastisment, followed by an answer. I've experienced embarassing public situations as a result of this (for him as well as me) and after the fact would come apologies, if necessary. If a deep conviction of his was present no apologies where offered. Notice a similarity here? (BTW, early in my marraige my wife thought I should go to counseling because I was surely damaged by my father's behavior!)

Human nature. We're ALL different, but some tendancies are similar. I work in a business that is dominated by Type A driver personalities. Meetings often border on hilarity while "opinion/edict" are expressed. All us Type C's nod in agreement and go then off to get things done. It takes all the personality types to make things work.

I grew up in and live in the current scenario. I know if I'm patient good things will come and no real harm is meant. It's just the delivery method.

Another two cents worth <img src="http://www.catsailor.com/forums/images/graemlins/smirk.gif" alt="" />

And Mary, thank you.

You remind me of my Mother. "Now if you children can't behave and get along I'll just have your Father take that and put it away for good! <img src="http://www.catsailor.com/forums/images/graemlins/frown.gif" alt="" />

Lets keep the forum.

I'm just proposing somebody else taking the reigns of this project then myself.

The F12 project will continue, I'm sure.

If nobody steps up to the plate then things will quiet down anyway and Phill and I will just get on with designing it.

Besides, I feel this forum could then in that case by used to great benefit to have the potential owners influence the design before it is finalized.

Wouter

You know, I've read and re-read this thread (and the other two related threads). I've considered different ways of taking some of the comments and outright statements that have been made against (and in favour of) various contributors. There seems to be very little goodwill being shown (in any camp). I've lost all appetite for this project in the present circumstances. Regretfully, I'll now work out something on my own that could possibly be considered a F12. I hope you all have fun bickering among yourselves.

Hey Wouter and Co, the best thing you guys can do is publish a F12 box rule based on the F16 project ( which I suspect is already complete but not published ) and then get on with your own projects, make a bit of money out of selling plans and set up your own website to support those plans.

Unfortunately there are do'ers and talk'ers in the world, the do'ers just seem to get on with things, the talkers seem to just well talk about it. <img src="http://www.catsailor.com/forums/images/graemlins/smirk.gif" alt="" />

Hey, logged on to the computer for the first time in a while. After reading the entire thread, Melissa and I are excited by the potential of this project. I don’t blame Wouter for being pissed off by all the nay saying. Wouter, we have no clue what you have done and what is not done. If we don’t have the details, we can not help, so do not ask us to.

I vote for Wouter to continue the project because he is the most capable person to get the job done right.

The only way I see this thing failing is if the box rule is poor. We need the initial design to prove the rule allows for high performance and a well balanced boat. Once the box rule is in effect, you can design your own boat or use Wouter and Phil’s design.

Matt

Hey, not bad...if we take Flatlander18's original topic starter in the general forum related to youth sailing as the inception point, then it only took 10 days for this whole small/cheap/F12 community boat development thing to begin, grow, diverge, and finally implode.

Good thing it's a Friday...now everybody go have a beer.

Wouter I admire your tenacity and “can do spirit”… working towards a goal with laser focus. I agree with you that to get a job done there has to be direct, concise communication of ideas.

What I have observed is that often a proposal is made… or questioned… and the one making the comment is personally attacked. I firmly believe there are some that “bait you in” just trying to get a vicious response, but most are not…they just have ideas or questions they would like to have considered… Things that they may have personally experienced that can help keep a project on track or avoid unnecessary set backs. Just as you bring to the table a degree of experience and expertise, so do they. Just like you… they want to be heard and seriously considered.

We all have different life experiences, that when combined, can give us the ability to do things as a group that could never be accomplished on our own. Think about it…collectively the sailors on this forum might represent hundreds of years of on the water experience… what a terrible asset to waste.

The project manager, along with his team, must distill this knowledge into a workable reality, there is not a lot of time for hand holding and touchy feely pleasantries…but one can be brief and to the point as to maximize effectiveness, without personal insults. Anytime the discussion moves towards a personal attack it moves away from the goal that both parties claim they are there to accomplish.

As a leader, you have to stay above the fray, you can’t afford to get in a mud wrestling match with everyone that tries to antagonize you…work on developing the ability to discern the difference between those that are genuinely trying to make a contribution, from those that are just stirring the pot. Ignore the pot stirrers and they will eventually loose interest and go away, keep engaging them and they will continue to haunt you.

As to writing off questions that have already been addressed…remember that there is rarely one perfect solution for a problem…the person that is “blown off” might just have a solution that comes form an entirely different field that you have no knowledge of.

I sincerely offer these suggestions for your consideration.

Best Regards,
Bob

Don't forget guys and girls Wouters natural language is in Dutch and not English, some of the gripes you Americans have ( and it is largely from those over the pond ) is just largely because of the literal language translation Wouter is using. For those of us used to people translating to English, this sort of thing is pretty normal.

And also remember written word, via internet or email, is the poorest form of modern communication. It allows no voice inflection, ever notice how you can tell the person on the other end of the telephone is smiling? It allows no facial expression, body posture, or gestures to help you translate the message.

Without all this physical stimuli, it allows your mind to wander, to input your perception of things such as tone of voice, read between the lines and derive and create percepted meanings.

Emoticons give some help in this regard, but we forget to use them and even with them a quickly typed message can never equal telephone or eye to eye conversation. Don't we think something like ten times faster than we can speak?

Are you guys trying to make excuses for Wouter or insult him? It certainly is not clear from the last two posts, which apparently were made by English-speaking people. <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

The dummy spitting is more interesting then the F12, Wouter has been annoying most of the forum users for years, just ignore him.
Remember Samevans?

Darryn

Sam Evans was one person, and yes Wouter has probably annoyed everyone on the forum at some time. BUT, Wouter has spent many hours helping regular members and newcomers to the forum over the years.

See the heading of this thread: F12 design and development

Does anyone remember the Dart 12 ? Laser brought it out 15? or more years ago. They demonstrated it at Dart 18 events and toured the UK with it trying to encourage junior sailors. I'm not sure why it didn't work - it may have been too expensive. I wondered if 12 ft was long enough, if it had enough buoyancy, but I think that the modern design of John Alani's and Wouter's hull has a lot more buoyancy than the old slim hulls of the Dart 12. My kids, at 29 and 27, are way past this cat, but I would love to see a Formula that sailors (fathers) around the world could build to (or buy) and so, start their kids Cat Sailing.
If we all stay cool, it can be done.

Dermot,
I think the answer is to come up with a super simple design to build. This would also be super cheap to build.
The quicker and easier and cheaper it can be built the more likely it will work to bring people/children into the sport.

I think quick, easy and cheap much more important than performance for the first timers.

Now if they are silly enough to come back to build another they will have some building confidence and sailing experience and hopefully both were pleasant on the first attempt and will want something much more refined.

Now most of us have had pleanty of experience with numerous boat designs and have developed a more refined taste that would not be satisfied with what a first timer would want.

To make something like this happen I think you need to get people together to do this as a social activity so they can be built in groups/numbers. Sailing clubs may be a fertile ground/venue. The clubs could run some adds and manage the building projects.
You could pitch it "dads and mums come and learn some boat building and provide a thrill machine for your young children".

Regards,
Phill

[/quote]
Sam Evans was one person, and yes Wouter has probably annoyed everyone on the forum at some time. BUT, Wouter has spent many hours helping regular members and newcomers to the forum over the years.

[/quote]

The frequency of Wouters posts and repetitive nature of the content is more advertising for F16 then facts about Catsailing that can help newcomers to our sport.
I mentioned samevans as he posted the same stuff about wouter years ago that users are complaining about now.

Enjoy your little boat guys, is anyone building yet?

Darryn

Dermot,

Can je dig up some info or pics on the Dart 12 ?

Would love to know more about it.

Especially the basic specs and anything that would give a brief history of the class or comment on how this boat sailed.


Wouter

<img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" /> Darn, I was hoping to keep that a secret <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

I'll give you guys a hint. With a boat this small, the right specs are absolutely critical.

Wouter

I had a look online yesterday and this is all I could find: http://www.multihullsmag.com/boats/boatlists/cats_up_to_20_feet.htm
I will look through some old files tomorrow and see what I can find. I think that it looked like a small Dart 18 and 15.

Wouter I got your PM. I replied, but your box is full. Anyway, I will check out the Dart 12 and see what I can find.

Phill,
I agree completely. Maybe when the grandchildren come along, you guys will have sorted the design out and I will have time to get building !

Dermot,
I'm taking about something simpler than the shapes Wouter and John have drawn.
A "Super Simple" 12 ft cat could be drawn up with building instructions in a couple of days and a couple of weekends to build plus painting if thought out carefully.
So I suppose you're right, it could be done by the time the grand kids come along.

The best thing would be if a big company with lots of advertising money supported it.That may be a bit further down the track imagine 2000 little cats spread around the globe advertising CATSAILOR or SUBWAY!!!!!
If only I owned a massive international company.
But I might be just dreaming?

Unregistered, please e-mail me: mary at catsailor.com

Phil,

Do you have a shape in mind, if so are you willing to share it with the forum?

Gareth

Phill is definately the man to talk to in the way of hulls and building them.

My hull plan is known, but more interesting is the fact that I spend by far more time designing the other parts. Here there are a few tricky issues that needs to be solved.

I must admit that I wasn't up to designing the whole 12 ft cat in only a couple of days. At least not one that would succeed on the crucial points.

Wouter

You know, this F12 did get my juices going in such a way that I started looking at something like this. I figured that for the extremely low cost of these craft a company could just buy 10 or 20 of them and do a major promo stunt with it. I dare not publically express the cost listing I have now as I just can't believe it myself but it is truely low.

But the boat have to look cool and exiting other a company like RedBull will not consider it and this company really does stunts like that.

And I figured one stage more. What if this takes off. How many would fit in a seacontainer ? Must we try to design the rules in such a way that it will be really inexpensive to ship them internationally. Say to one of the Caribian islands.

I now got the package down to 36 per 40 foot container with the F12's all packed in their standardized (card board) boxes. This can well be the boxes in which they were delivered to the customer initially. I'm getting close to putting 48 boats in. Result : Shipping your boat to an event to anywhere in the world would be between 200-300 Euro's if the container is stacked full.


Another reason for this effort is so that mass producing these boats in say Asia is viable.

Wouter

Gareth,
I'm both encouraged and discouraged by what has been going on in these discussions. So much enthusiasm yet still so much bickering.

I have been trying to work out why this is so. I think apart from the personal differences hear I think we may have two completeley different objectives.

On one hand there is a group that just want to get young people into the sport. Mostly people that you would not hook otherwise.

Then there is the group that are in the sport and want to get the best they can to introduce their own offspring to the sport or give the young ones they know in the sport the next step in performance or just design the best performer given the anticipated rules.

So in answer to your question I have two hull shapes in mind.
One will perform well but is essentially a fun boat that can be built in a very short period of time at very little cost.
The second is a more refined craft and given that I still have a desire to maintain simplicity and even with the physical limitations in this size it is a race boat. The race boat is for experienced kids and light weight adults.

The first shape is aimed at bringing people into the sport and if push comes to shouve could be built with a knife, screw driver, saw, plane, hammer and tape measure.
The magic in this is not in the refined hull shape but the method of construction, time involved and cost.
I think this boat will still give the newcomers what they need to get hooked.

So rather than share this with the forum and blow more hot air. I will try to clear some time in a few weeks and build it. Documenting both the time and cost. I need to build an F18 plug but straight after that I'll get it done.

It's time we saw something we can touch.

Regards,
Phill

I agree with this assesment. And as such I think the Formula setup of the class is key. If it were an OD then we would have to compremise between these two conflicting setups.

In a formula structure we can see both groups contribute to the class as a whole and more importantly the quick and dirty setup only has to different from the full force setup in the hulls. This means that while youngster is sailing and after the parent has evaluating the childs commitment to sailing is as sufficiently they can upgrade the boat with new and more performant hulls while just planting the rig and rudders over. This will save a bundle. I envision to old quicky and dirty platform to be moved on to another parent/child and thus grow the class by small steps at the time.

Wouter

Wouter,
There is nothing dirty about it.
It is just simpler and with simlicity comes compomise.
The simpler sollution in this case just has different advantages. Advantages that I think will be more inclined to draw people into the sport.
In drawing them into the sport it is more oriented towards fun than performance. When their prefernces shift towards performance you can then look at the more involved sollution that will give that added performance.

I'm taking about a sollutiom more focused on ease in the construction phase and fun on the water.
The other sollution is more about refined performance.

I agree that the formula concept will embrace both if the formula is well written.

Regards,
Phill

I understand and I was with that scheme from the beginning.

Forgive me about the "Dirty" word. <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />




True.

But I would like to underscore that when designing the basic underlying structure of the F12 we should be fully focussed on maximizing performance given the strict limits (simplicity/cheap). Because it is far easier to make a fast design more "fun" then making a "fun" design faster.

Wouter

Are you guys trying to make excuses for Wouter or insult him? It certainly is not clear from the last two posts, which apparently were made by English-speaking people.

Perhaps Mary we should have a translation from Queens English to American English <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />

No resin or glue?

Gareth

The mono 420’s have centerboards, the Optimist and Lasers have dagerboards, all popular with youth sailing teams should they also be considered for the F 12?

Regards,
Bob

Well a laser daggerboard is probably expensive. We will need 2 custom boards, so it is not in line lowest cost approach.

For now I want to try doing without daggerboards or centreboards but if we need them then they are easily added to the hull. Sadly, as Matt says, against added costs and complexity. As we'll have two on the F12, will be much more hit by these then a monohull.

Wouter

Can we talk about this single control line rule? It seems to me that this will work well upwind, but on initial view it seems we may end up with quite a bit of twist off downwind. If that were correct, this would mean that we are no longer sailing to VMG downwind.

What am I missing? what is your plan?

You're missing a previous post (buried somewhere back there!) when Wouter mentions a traveller system using Ronstan RF188 becketed blocks and a 4mm control line.

You are correct.

But while this issue has not been discussed publically yet (except for the traveller setup) as solution is worked out anyway.

There are two versions : one uses a kicking strap (non-adjustable) and the other uses a ram vang (non-adjustable)

These have a use upwind as well. By preventing the mast from bending back too far when the mainsheet is released the sail should tack better in lighter winds. Additionally this limiter prevents the boom from rising beyond a certain level and thus reduces twist when the sail is fully boomed out.

But for most course John is right the F12 will have a traveller system, one that only costs 37 Euro's in DE-LUXE version and 4.5 Euro's in the cheap but effective setup. this will take of most needs All the way up to reaching a little deeper then a beam reach.

It is many more things but I'm not going into detail on this here and now.

But I can assure the readers here that teh basic idea is to give the F12 significantly more performance then the alternatives out there (like the wave) by providing much better sail control. The only limit to this is cost but even the DELUXE version costs less then 200 bucks overall. While providing full control in light, medium and heavy winds with draft control devided in lower halve and top halve and twist control for both the light and heavy winds.

Pretty much the design goal I had was this :



Light winds :

relatively shallow draft in the sail with alot of twist along the leech.

medium winds :

10-15 % draft in the sail with a tight leach. Here the mainsheet mostly controls draft in the sail and very little twist.

heavy winds :

shallow draft in bottom part of sail with almost no draft in the top and a leech that is twisting off. But with the behaviour that releasing mainsheet first increases twist and hardly any draft. If possible releasing the mainsheet should first increase draft then allow the boom to swing out and only in the later stages allow the draft to increase.


I think I got that worked out to a large extend.

Wouter

Is a windsurfing rig still in consideration for the F12? If you take a modern windsurfing rig and pop it into that welded bracket as shown on the land sailor...all the tweaking is done when you rig up the sail at the beach...other than maybe a traveler...and the main sheet what else is there left to do? I am really excited to see what a modern windsurf rig could do on the F12...IMHO the windsurfing rigs (sails/mast/boom) are light years ahead of the sails the catamaran community has in use.

The interplay between the sail cut/mast flex/boom stiffness
makes the windsurf rig feel alive. I would go so far as to say that most boat sailors would wet themselves if there boat had the 1/2 the gust response a well tuned windsurfing rig has. A gust hits and its just pure forward acceleration.

...ask anyone who windsurfs at a near expert level (short board) who is also a cat sailor... they will confirm this.

Regards,
Bob

Allow me to respond to this question in a short to the point way :

-1- What do windsurfer do when the wind changes in strength ?

-2- How many suit of sails do windsurfers have to be able to sail whenever they want ?

-3- How well does a windsurfer transition from pure upwind work to downwind with high vmg ?


Correct me if I'm wrong but the windsurfer rig may be lightyears ahead of catamaran sails, but only at a very narrow windstrength band and with only a narrow band of courses.

Maybe somebody should educated me on Formula surf boards, I hear they do better ?

But it is often forgotten that a sailboat rig is required to operated well at a very wide windspeed range and on any course between pinching upwind and runnin square downwind.

Sailboat rigs can sometimes have amazing flexibility in flying shapes produced by adjusting a few control lines while racing on the water. I haven't seen surf board rigs do anything like that.

Am I wrong ?

Wouter

Hi Wouter

“1- What do windsurfer do when the wind changes in strength?”

They use to have to change sails every 6 mph or so…now you can go out with a top quality sail and hold it down in wind that would have required 3 or 4 sail changes 15 years ago.

“-2- How many suit of sails do windsurfers have to be able to sail whenever they want ?”
I use to have an 8.0/7.0/5.7/5.0/4.5/4.0/3.5/3.0 in the late 80’s that would let me sail from 5mph to 40 mph winds. But the 5.7-3.0 were for surf sailing…where it is much more important to be dialed in with the perfect size. Back then just for recreational flat water it would be more like 8.0 6.0 4.5 Today you could easily hold down a good race 8.0 from drifting conditions to well over 25 MPH wind on flat water and the proper board. Basically all the conditions that catamarans are regularly sailed in.

The cut of the sails and the way they have tweaked and tweaked the sails and sail mast interaction is just amazing.

3- How well does a windsurfer transition from pure upwind work to downwind with high vmg ?

That’s a function of the board shape (rocker/bottom shape/rails) and fin being used as well as the sail itself. Dead down wind is not its fastest point of sail but sailing powered up on a deep broad reach will get you downwind at break neck speeds for sure.

“Sailboat rigs can sometimes have amazing flexibility in flying shapes produced by adjusting a few control lines while racing on the water. I haven't seen surf board rigs do anything like that.”

My Friend Mike Gephardt three…(or was it four?) time Olympic sailboard campaigner (one silver, one bronze) has had adjustable outhaul and downhaul on some of his race boards that I have seen to address just the things you are proposing…

Please don’t take my enthusiasm for windsurfing as a knock on catamaran sailing…I love them both…it just that windsurfers has been so much more open to new development than boat sailors. So to have a chance to take what I feel is a vastly more developed rig and apply it to a catamaran gets me all excited.

One lesson that windsurfing surfing seemed to grasp right away it that everything is interdependent…and although that sail design might not have worked last year, it works great this year because the board is been refined to capitalize on the sails strength or the fins improved which allowed the sails to be cut flatter and still have the power to plan out quick…or that setting on a softer constant curve carbon mast allow the sail to breath with every puff but reset to its static shape much more quickly. Large square head sails with tons of downhaul that allowed sails to triple there designed wind range. Its not that Cat sailors are unaware of this, it just that the windsurfing community has put more a lot more energy into R&D . Every variable affecting every piece of gear was/is on the fast track so that it just keeps getting better and better at an accelerated pace.

On the other hand most Cat sailors seem to put “protecting their investment” over any desire to propel the sport to the next performance level. Every possible improvement is seen as a threat of making their cat obsolete.

Shake loose some of the cobwebs and fire up some cat sailors to consider something beyond the status quo…LOL..push the limits till they squeal like little girls. I can’t wait to see were we end up.

Best Regards,
Bob

That is a very true observation in my opinion. The cost of cats is much higher than windsurfing, so it is understandable tough. Balancing cost vs development is a very fine act of performing on a slack line, with entrepreneurs trying to find loopholes in the ruleset all the time. A different view on the same problem would be "do we want the sailor with most money to win, or the best sailor". The answer is usually trying to control development, so it happens slowly and in increments. Not in large jumps rendering lots of boats obsolete and uncompetitive. And what about spending money on the latest "hype", just to discover that it did not make you any faster <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />
The C class is an example of an class which nearly have developed itself into extinction by not limiting their development over the years. Those rigid wings are drop dead sexy, but wildly impractical for club racing.

I'm not ruling out windsurf rigs and that has been my personal opinion from the beginning.

As the situation stands a windsurf rig can be fitted to the F12. I see no need to forbid it.

Still the designing I've done so far does not enclose optimizing a windsurf style rig. The reasons for this decision are as follows :



-1- Cost limitations

A class 5 mast can be homebuild by an absolute amatuer.


-2- Sail efficiency.

A sailboat rig at this time can have a significantly higher aspect ratio then the windsurf rig.

I'm not sure that the current lower aspect surfer sails can easily be scaled up while retaining their excellent behavior.


-3- A cat is significantly different from a surfboard

In my experience a catamaran has a much lower need for gust response then both skiffs and sailboards. Having the sail respond to a gust while it is not necessary means losing performance. At this time I feel a more conventional catamaran rig is more suited to getting optimal performance over the full range of conditions from light to strong. It not about holding a sail down in all conditions, it is also about getting maximal performance in all of these conditions.


-4- Windsurf sails don't really have a mainsheet system that affects the leech tension.

In affect with a more conventional rig you have one extra tuning control. With f12 you have two more as the traveller setup can be set to windward (something normal cat traveller systems can't do).


-5- I'm personally not experienced in windsurfer sails.

I understand catamaran sails to a large extend and surf sails to a much lesser extend. In effect I do what I know best. Maybe somebody else needs to do the design work involved with F12 windsurfer sails ?



But again these are not reason why the surf rig is disguarded (it is not), they are only reasons why I'm not developping it further as opposed to the class 5 landyacht based rig.

But if anybody else wants to spend some time on this I'll be very interested to hear the results.

Wouter

I am trying to persuade a windsurfing school and a holiday company to test my current boat, which has a biplane windsurfing rig setup, both these companies have experienced dinghy and windsurfing sailors on their staff. The feedback should also apply to F12 windsurfing rig setup. I am hoping to get a better understanding of which sails work best. I will share the results with group.

Gareth

That'll be great thanks.

Wouter

“-1- Cost limitations

a class 5 mast can be homebuilt by an absolute amateur.”

>If you are talking about a new carbon mast, I would have to agree with you…but there is a lot of used equipment on the market…especially now that kite boarding has taken off and a lot of windsurfers have made a switch…at least in my area.


“-2- Sail efficiency.

A sailboat rig at this time can have a significantly higher aspect ratio then the windsurf rig.

I'm not sure that the current lower aspect surfer sails can easily be scaled up while retaining their excellent behavior.”

>The windsurfer rigs have been all over the place in respect to aspect ratio, but have settled into the sweet spot about twelve years ago after trying all the extremes, including much higher aspects than are available in the current offerings.

>For a while they felt that longer boom length with lower aspect was needed for low end power, and then went to extremes with high aspect for speed sailing to “reduce drag”. In the mid-eighties Gastra sails came out with “camber inducers” to force an air foil shape into the sail which gave a lot of stability to the foil of the sail…particularly noticeable in larger sails when sailing thru a lull, and building on the use of full length battens and the RAF (rotating asymmetrical foil) shape sails that Neal Pryde was offering at the time.

>Fast forward to the nineties… the sails went to monofilm and the cuts became better. Centered on a flexible yet quick resetting carbon mast (which allows the sail to maintain its ideal design shape a larger percentage of the time) with very stiff carbon booms (outhaul stability, if the boom flexes the sail draft increases and moves back…now you are looking at a “face plant”)

>Windsurfing moved away from the pin head sails and started putting more and more area in the head. By using a large square top design it allowed them to put more area in the sail for power to get up on a plane sooner as well as lowering the wind speed necessary to plane in the first place. The older style sales (especially in the larger sizes) quickly got out of control… but these new sails were cut flatter and were designed to have a complexly floppy leach at the top 30%+- of the sail. As the sail powers up, the top of the sail twists off and the draft (power center) moves down and forward…turning a gust into pure forward momentum. So they achieved a “best of both worlds” scenario. More sail area for light winds and a “self regulating” sail in high wind or gusty conditions…When properly tuned it’s like an automatic transmission for your car.

“-3- A cat is significantly different from a surfboard”

>I agree…this is where it could get interesting…to see if they are as different as they appear…

“Having the sail respond to a gust while it is not necessary means losing performance.”

>Again I agree…but at least when used in conjunction with a properly designed sailboard the sail design has been so dialed in that there is very little wasted energy. What would have blown you over, or caused a draft shift to the rear of the sail causing an “over the handlebars” situation in the past now gets converted to pure forward power and very balanced feel.

“At this time I feel a more conventional catamaran rig is more suited to getting optimal performance over the full range of conditions from light to strong.”

>That may prove to be the case, but we won’t know until it is seriously tried…the possibilities are exciting if the positive attribute will transfer over to the f12.

“It not about holding a sail down in all conditions, it is also about getting maximal performance in all of these conditions.”

>”Holding down the sail” was more in reference to the idea that, as in the past, windsurfers are forever changing the size of their sails to meet the changing wind conditions…I might add most catamarans are doing little more than “holding it down” in 25mph wind wouldn’t you say?


“-4- Windsurf sails don't really have a mainsheet system that affects the leech tension.”

While you are correct in saying that they don’t have a mainsheet system that affects leach tension… The outhaul tension, in conjunction with the down haul controls the leach tension to a very fine degree. Top of the line windsurfing sails are extremely “tunable”. This is generally done on the beach, however as I stated in my prior post some racers have used “on the fly” outhaul and downhaul adjustments to give the sail a fuller shape when course racing on downwind legs.


“I understand catamaran sails to a large extend and surf sails to a much lesser extend. In effect I do what I know best. Maybe somebody else needs to do the design work involved with F12 windsurfer sails?”

>I would have loved to be more deeply involved in this aspect of the F12 but family/business restraints have my plate overflowing…that said…any experience I have in this area that can be of help I freely offer…

>One of the coolest things about the windsurfer rig is… if can be set up with a way to accept a standard windsurfing mast base, you can try an endless variety of sails by just releasing the spring clip and snapping another on.

>Most serious sailors have a whole “quiver” of sails of the same brand and style, so you could see exactly how far to push the size limit before it became a point of diminishing returns. Same way with sail shape/style.

>It might be worth approaching some of the top windsurf sail manufactures, or a local windsurfing shop to see if they might want to become involved by offering sails/masts/booms/bases for the prototype in exchange for advertising exposure. I am sure they are feeling their revenue fall off drastically as Kite boarding as taken a big bite out of their market. Might be an easy sell with the prospect of opening a new market for their equipment… Wouter… with your track record with the F16 Class you might have the credibility to make that happen…

Regards,
Bob

All very interesting. Should be tried I agree.

Talking about plates overflowing ... I know another guy who is in desperate need to make a few difficult choices.

If I did have the financial resources at this time I would have a set of F12 hulls made for me and then would do the first test sailing myself using my landyacht gear and the ruddersetup of my F16.

But I don't have sufficient funds at this time and I really don't have time (this year) to build the hulls myself.

With this situation it will be impossible for me to try and get the local windsurf guys to give it a go. For that to happen I need to at least provide them with a test platform. Also as a proof of seriousness/dependability.

But I do have a network and maybe I should do the rounds and see what I can arrange .....

Wouter