Opinions on how to improve today's cat- designs

As we all wait for the new Hobie F18, I want to hear everyone's opinions on how to create a new and better cat design. If the Hobie designers turned to YOU for advice, what would you say?

With the introduction of the capricorn and the infusion, there has been quite a change in design philosophy from the older Inter F18 and the Tiger. While the Capriocorn took the whole wave piercing theory a step further, the infusion has loads of volume around the front beam, thus preventing it from stuffing it when the wind is up. What do YOU think is the way to go?

I know all the F16 guys will say "make it 70 kilos lighter, and being able to sail one or two up". That's not the point here, I wanna hear propositions that can be applied to all cat designs and sizes...

Lower the price.

I would tell Hobe to go and negotiate a deal with Phill Brander about the Blade design and put him on the design and production team. Honestly.

I think the way forward is with drag reduction from the whole package, easier/better handling/trimming and doing a couple of prototypes before comitting to full production.

I dont know if there are sailing prototypes of the new design though, so I might very well be completely wrong about the last point.

Sorry to hear the impression you got of the F16 class. Hope we will be able to redeem ourself.

Jimi,
this is a very interesting question. There have been times when manufacturers took the "what the client wants/think" approach (not reffering necessarily to cat designs), but this makes me wonder: why on earth do they employ designers that haven't already improved "today's cat designs". I mean: for every boat that comes off the production line - there is a designer behind it - why isn't he doing his job of improving things ?

I think I can speculate on why: they are designed mostly by economists rather then listening to good designers.

Scenario: manufacturer makes a study how to improve designs by asking sailors. They make a list. List goes to designer - works great. Designs goes to financial department. Design goes back to drawing board for modifications. You end up with a boat that hasn't got the "improvements".

Manufacturers (most of them) are lead by profit, the margin of improvement has to be parallel to improvements in manufacturing techniques that makes the design economically feasable. As some of the manufacturers still use technique from the 80' then...how can you really improve?

If we are only reffering to hull design - as long as they do employ designers for that (that probably get paid a lot) why are we to bother thinking about it ? Possible answer :they don't do new designs too often, just "face lifting" models from time to time. "Face lifting" is not an improvement, it is a marketing strategy to sell something old.

I'm not familiar to Hobie or other manufacturers innovation an improvement time table, but we should start analizing it.
Most of the "innovations" and "improvements" out there are much more probably updates of major design flaws.
Can we spot some of those and see if they were marketed updated as major innovations or improvements ?

The best way would probably be to start from scratch. New designer, new model. But major manufacturers will only put as much as little "new" into the boat so they can sell future models as well.

Too long post. Sorry. Got carried away.

Regards,

'New and Better'?
New isn't always better - just different. Almost everything is a compromise. You could probably design a blisteringly quick boat for certain conditions but it may be extremely difficult to sail consistently well. Many things appear because of fashion or the desire to create something different to generate new boat sales. If a front of the fleet private owner changes his boat every three years is he going to replace it with on older design or the latest so called improved boat? Stick a front of fleet sailor on an old but perfectly serviceable boat and chances are he's still going to be at the front of the fleet. The skill is knowing how to get the best out of your equipment and sailing it accordingly. Trying to match the performance of another design is normally not sailing yours to the optimum.

Possible area for development:
-Control/adjustment of foils
-Automatic mast rotation adjustment to mainsail trim.

Suggestions on others??????


Cheshirecatman

All design is a compromise. All design is an evolution of a previous design. Design is an iterative process, particularly yacht design. NOONE gets it correct straight out of the box, if they did there'd be no need to tuning. The best you can hope for is that the person paying for the product is "happy" with the purchase.

What is your definition of "better". Cheaper may be better...faster may be better...faster in light winds may be better...

As a designer, the question is way too vague.

an old staple of marketing is that all the customer wants is last year's model cheaper

as that would cut into profit margins the challenge for the maker is to use better production techniques to make some thing cheaper and hence more profitable. as this usually requires new molds etc. it is a good idea to also to make the bits better by either being lighter or of improved function.

i'm happy with my 26 year old cat, it's heavier than it could be but seems very strong.

if i had the cash for a new boat i would be looking for something lighter that could be sailed solo

something like a 100kg A cat that cost no more than a hobie16

• Don't put one of those spindly wing mast bits of nonsense onto the new boat. I say this as a sailor...If I was selling the boats I'd be all for wing masts and the parts income they generate for dealers.
• A little more volume upfront (Infusion style) would make the boat a little less tricky to sail down wind in a breeze (a little harder to stuff).
• Make it sexy looking with some new feature to fool the gullible into thinking that this boat wins championships on its own (forget about those two primates pulling the strings and pushing the tiller).
• Other than that I'm not a naval architect and reckon the best thing the designers could do with my advice is to politely ignore it.

Chris.

You joke, I think, but that would be the best thing for cats...A fully competitive F18 or F20, with target prices of 10-12K. While it may seem impossible, if 'economy of scale' were possible, it would be a boom to the MH class. (This of course, presupposes that an untapped market exists for selling the boats.)

Lowering weight (< 150 kg/320lbs) and reducing drag would be good.

However, strongly reducing tendency to pitch-pole would be the biggest improvement. That would enable us to push much harder.
And it would draw many more people to cats. A lot of people are reluctant to sail cats for fear of cartwheels.

So I think T-foil rudders (that may be tilted up for beaching) and flatter bottoms (as on the Infusion) - both mesasures to reduce pitching - are important developments.

(And, if someone could find a way to reduce the space taken up in the boat park, all arguments against cats would be eliminated. Almost.)

Stein

Hi Stein,

enjoyed watching you on TV last friday

What is up for the Taipain5.7 next season? New sails and a snuffer?

ncik said:



Very accurate.

Right now, I think "better" -- to define "better" -- is getting more people to buy the product.

The simplicity and value of jet skis has replaced catamarans at their level of use here, IMHO.

What is missing is something in the 16-foot range that is not over-technical, is moderately priced, and, as Stein says --



The performance cats (they are not beach cats!) are too technical and too risky for popular sailing.

The rotomoldeds have all the right features for popularity except extra speed and agility. The Wave is a 14-footer that is about right (and I assume this is why Rick and Mary like it), but its speed is limited. The Getaway is a fun boat, but not agile enough.

What is missing is something is the middle category between the fun, beach cats and the performance cats. (The H16 is a performance cat IMO.)

The Pearl (greeeeaaat name choice?!) or TheMightyHobie18 may be the right choice in Europe but not here.

The catamaran is moving from a fun boat to a yacht status, in my opinion. And that is not good. $11K for an N20 mast proves it...

Seen the Topaz 14/16?

Cheshirecatman

Swedish bikini support crews?

not my quote...



that would be "better"

Better margin for the dealers, so we don't have to live in our vans down by the river;) Although it is kind of nice down here...

J

I sailed the Topaz 16CX (top of the range with better sails and a spi) solo once. It's a fun boat, but it needs a lot of wind to move. In the 7-8knts I experienced at the time it was a dog... In retrospect I should have rigged the jib in addition of the main.

Compared to a F16, the CX is more robust (rotomolded hulls), has less sail area, is 40kgs heavier and has no boom nor daggerboards.

However it cost only(!) £6000, for reference a double handed Stealth is £9200 (could be more if you want a self tacker or carbon foils), a Hobie 16 with a spi is £9700.

Slightly off topic...

It will be interesting to see how well the roto-moulded boats hold up in the long term. On one hand they can handle a bump here and there, but this could mean ppl treat them worse than optimal hence reducing their life span.

funny how the Tiger is still competitive, maybe newer isnt always better

More boyancy in bows
Less in transom to keep butt from being lifted and driving bows.
Plenty of clearance between beams and waterline, particularly rear beam.

KEEP IT SIMPLE

I really like the Tornado c/boards. Whilst they are not quite as efficient upwind. Not having to put them up on the downwind saves plenty of time allowing you to wind the big fella up earlier. Also cleans up the deck. Do not have a board getting in the crew's way or a sharp trailing edge welcoming a painfull strike if you slide into it on a nose dive. Perhaps revise the shape of the boards. More of a regular dagger board shape...... Perhaps like the Taipan 4.9 / 5.7.

Wide beam, but quick release beam set up so you can trailer dismantled. Purpose build a trailer with a huge gear box which runs full length of trailer and design a quick, no tie system to hold the hulls on top. Perhaps an upside down cradle that swings over the top and locks the hulls in with a pin.


Consider multiple rig sizes for varing wind strenghts like the Skiffs.

2 complete rigs.

or 1 mast with a step

or with one mast and allow the ability (within class rules) to select main sail size before a race. 1 x full size and another partial, flatter heavy wind main.

Ah, two piece mast of course. How often have I not wished for that to go with the two piece bowsprit (or telescoping bowsprit)

If a Hobie 16 is being referred to as a performance cat do you really think an F16 is a suitable boat to compare the Topaz to? If Yves Loday wanted to design an F16 we all know how easy that would be.
The Topaz ticks the boxes of what was previously suggested and a bargain for any US buyers with the current exchange rate.
Now, if it was to be built out of high performance thermoplastic matrix composites(HPTMC) instead of being rotomoulded, and had daggerboards you then start working towards a low maintenance performance cat.
However, talking about improving cat designs, how about HPTMC masts?

Cheshirecatman

How light, flexible, durable and pricy would HPTMC masts be

Performance - designed-in as per a carbon/epoxy matrix mast with additional benefit of being less fragile. The potential benefit is using thermoplastic lends itself to cheaper volume production, but tooling costs? I suspect they could also be produced over a male mandrel but surface finish may not be as high as people may like.

Cheshirecatman

The spi pole on my stealth is made of two piece of carbon tube sleeving into each other. I don't know why it is done that way rather than one big pole, but as it makes it possible to fit it into my trailer box I'm rather happy about it...

At the time that's what I was comparing the Topaz with. I wanted to replace the 5.2 and I was looking at what to replace it with.

I briefly considered the Topaz 16 and the Dart 15 as possible alternatives. In the end I went for a F16 because that's one of the largest and most active fleet at my club, and it is way faster than any rotomolded boat.

Lot's of people on this site want to refurbish old boats. I think a clearing house for old, spare parts would be helpful in increasing participation.

If you want to invent something, how about a fool-proof righting sytem. All the current systems have limitations, usually limited to the skill (or body weight) of the user.

I use the most basic system: a line stowed in the tramp pocket and attached to the dolphin striker. On an idyllic day, this system is nearly perfect. As conditions deteriorate, and fatigue sets in, just climbing onto the hull becomes a chore. A system which could be deployed while still in the water would be safer, easier to use, and most importantly, would add peace of mind for the sailor concerned about his crew.

How about some design goals.

Make them cheaper - a 25k i20 is obscene.

Make them lighter. - There is no reason a f18 has to weigh 400lbs.

Make them more durable - and make the components durable, get rid of hollow rudders, and make them kick up.

Make them easier to right, (Tikipete's right on)

Make them more comfortable to cruise - Add wings or extension seats for when you dont want to trap out, so you can easily take friends and family and not worry about if they can trap out.

Make them easier to rig.

Make them fun to sail - bigger rigs, lighter weight, more durable all add up to more fun, less fuss.

So you want to turn the F18 into a lightweights boat? keeping the weight up not only negates the expense of using 'exotics' but enables a good range of crew weights for competitive racing. Over the years F18 has succesfully attracted sailors from a number of other classes due to its non-extreme rules. It IS a successful formula. Want a light boat? F16, A-class, Shadow.......

Cheshirecatman

First of all, I dont have any desire to make the f18 lighter, it was an example. We were talking about design ideas, not the f18 class specifically.

But since you brought it up, making hulls out of standard production materials that weigh much less than the current f18 hulls would be easy.

The guys from Madison, CT took an old Rorche Acat mold and made a f18, and they had a HARD TIME making it weigh enough. Overbuilt doesnt add anything.

I used to joke that when Bimare was making their f18, they were going to take an HT hull and pour resin in it. The HT hulls arent exotic, polyester resin and fiberglass, and they are dramatically lighter than the f18 hulls.

So, yes lighter is a goal that I would recommend to improve today's cat designs. I wouldnt change a thing about the f18 class, its doing fine the way it is.

Technically much is possible but often the consequences are not desirable. The benefit of boat weight negating crew weight advantages has created a wide playing field in f18. When creating a very light boat the crew weight becomes a greater factor and you have to look at the appeal to the cat sailing populace.

Cheshirecatman

Wow, thats a stupid excuse for a heavy boat.

A heavier crew has an advantage in big winds and a lighter crew has an advantage in lighter winds no matter what boat we are talking about, but that still doesnt guarantee a win. Go look at the Acat fleet, Lars is one of the heaviest guys in that fleet at 185lb and he routinely beats everyone else weighing in at 150-160lb.

Besides the f18 class has allowances for differience size crews with the differient sail areas.

RE: Tornado Alive--- This is keeping it simple? WOW! Brain damage has been documented!

"No boards, Huge trailer box, 2 complete rigs, inverted mount on trailer..., 2 or 4 mains to choose from"

the reheated nacra 5.8/580 has swing up boards

http://www.nacra.us/580/580dex.htm

roto-molded kayaks are very very tough and last very well cart wheeling off roof racks etc. mine got semi crushed under snow but an afternoon of hot sun popped it all out

of course they start to look like crap when the scratches get all furry but i bet they last longer than people want them

The Topaz looks something like the Morelli & Melvin Escape Cat, pic above. Which is no longer on Escape's list, apparently sunk from sight and Escape's site (It went out of US to Nacra Europe as the Playcat.)

I think cat dealers need a bailout from Congress. No more living out of vans down by the river. Just sail your A-cats to a hearing tomorrow! (Like the GM folks did their private jets!)

When I watched the video on the 40th regatta that JW posted, it was interesting to watch young Hobie Alter in an old film drawing out his cat design in the beach sand. And then the older Hobie saying that that is his drawing board. Plus you had to check with your buddies to make sure they liked the boat first.

Reminds me of Steve Wozniak working out of his garage, designing the Apple.

So, that backyard, garage approach to cat sailing, hasn't it always been a big part of cats? And is it going away?

I'm coming to the conclusion that it is pointless trying to improve cat design. It seems that many sailors either fail to notice developments or are too blinkered to accept them.

Cheshirecatman

With all the arguments about weight I'm starting to think that maybe adding a lead keel to the F18 would level out the playing field even more... Just like it has on Mono's. Reckon that would see us back in the Olympics in no time too!
To tell you the truth, I think sailing should be all about brains, not brawn. If a level playing field is desired in OD racing I'd prefer crew weight categories, like they have in boxing or wrestling.
As to heavier boats being cheaper to produce, I don't believe it, unless they're made prom paper-mache(sp). All that resin has to cost a lot, I'd rather pay for some extra carbon than 20 extra liters of epoxy!

This thread is supposed to discuss proposals to improve cat designs !

Jimi specifically asked you not to reiterate all previous arguments about weight.

What do we now think is the optimal hull shape?
What about planing hulls?
What is the optimal board shape?
New ideas for sails?
What about lifting foils?

And ideas that makes life (cats) easier ...?

Stein

Thanks Carl.... Appreciate your comments ....... Unit!

I an looking at a big beam cat with a lot of horsepower that can be driven very hard off the breeze, un rig and de-rig quickly and be a pleasure to sail on the water.

"Keep it simple" ie

clean deck layout
quick release beams. - so you can have a big beam cat but de-rig quickly.
Big trailer box = all your gear can fit in easily and quickly including spin pole. (can mount racks inside for all gear)
Quick clap down "no tie" trailer
No boards (I did not say that) - Low profile boards so you dont have to keep rasing and lowering like on the F18. Taipan 4.9 and 5.7 have low profile boards as with the Tornado. You do not lift them when you turn downwind on a spinnaker run. Time wasted rasing and lowering would be better served getting the boat up to max speed and maintaining it for as long as possible. Also cleans the deck up not having boards protruding out top.

All this in aid of speeding up rigging and derigging. Dismantled = less windage trailering and narrower beam,

Rig combinations do take it to another level but imagine a cat you can race when it is cranking 30+ sustained. Perhaps best idea would be just 2 mains. The modern cat rig can depower so efficiently compared to it's monohull couterparts, more than 2 rigs would be unnecessary.

Others may have different ideas in what they would like to see in their beach act...... But this would be my ideal ride. I am very fond of the Big T.

I suggest you find a class that welcomes such keel development and go and prove your weight theory. Then try to sell it. Love it or hate it the F18 formula has proved extremely successful in developing class racing around the globe. Lightweight boats of various sizes have been built. There are obvious advantages to the singlehanded sailor which is where the F16 and A-class find favour. The M20 has proved to be a capable boat, at a price. The f18HT??????
If the F18 were to change and reduce the weight of the hulls and allow a carbon mast what would be the result? A substantial number of boats no longer being competitive and depreciating heavily, sailors leaving the fleet due to cost of upgrade and basically no longer being a competitive crew weight. Costs are contained when there is volume. You only have to look at the N20 mast issue to see what happens when low volume effects product viability.
If you want to 'develop' catamarans you need to be able to prove the benefits to sailors otherwise the idea is dead. With the advent of numerous high-performance skiff dinghies catamarans have changed considerably over the last 20 years. Racing cats are now almost universally spinnaker equipped and use daggerboards. That is development, and has been accepted. Don't knock what works. You do a disservice to people that have worked hard to develop the sport. Maybe the boat weight issue can be addressed by adjustable beam but until someone can prove it who will buy into it. Even then it may end up being a 'good but never made it' boat.

Cheshirecatman

Though I disagree with you Cheshirecatman when saying that weight limits crew weight (the Taipan 5.7 uses NONE of the so called exotic materials, it still weighs in under 150 kgs, and is was originally targeted at crew weight <150 kgs), that was not the point with this thread. This thread startet out specifically pointing out that weight not was a parameter that could be discussed, that's exactely why I took the F18 as an example!

Start your own thread if weight is what you want to discuss.

So what do you think Jimi, and have you found anything useful in this thread?

Jimi, I have no gripe about boat weight and my comments were only made in response to claims over the F18. I know you will always get people (usual suspects)discussing weight as you initially predicted. The weight issue works within the f18 design parameters, but such variability and acceptance still has to be demonstrated in light weight boats. I think a 5.7 was modified to meet F18 rules and still won texel. If having the weight is not an issue look to what is. There have been valid comments made in this tread. Let's hope the 'negative' posters do not discourage positive discussion.

Cheshirecatman

Improve sheeting systems. The fact that we're all still sheeting from the rear beam is somewhat silly since most of us have our crews triming main. At least market systems that allow both sheeting locations.

Make further strides in uncluttering the running rigging. Overtime, my N20 tramp has gone from simple, to spaghetti central.

Create a telescoping tiller system that doesn't use a crappy universal joint to connect to the tiller crossbar. I recently went to a solid tiller with a typical rubber connector and the response feeling was incredible.

Kick-up daggerboards. I like my N20 boards. I wish they'd kickup if they smacked a seaturtle.

A sarcastic cat list:

1. More pitchpoling!
2. Longer daggerboards/centerboards. Whacking sandbars and sea turtles -- and tearing up a $15K investment by simply cracking a sandbar ONCE. Two thumbs up!
3. The heavier the mast, the worst mast-raising setup!
4. Rope everywhere!
5. Vague trailer and beach wheel designs. Crack up the boat in the parking lot while off-loading onto beach wheels!
6. Nothing under 400 lbs!

Undecided, cat sailors who are experienced, want this:



There are two wish lists "to create a new and better cat design". Both wish lists are for performance cats. One is for experienced, the other at an entry level performance boat that will sell in volume and make bigger dealers.

No doubt for me that it is something in the 16' range, as I harp.

There is no doubt this is true.

Well, the kids did a great job on that boat. Very impressive. However, one of the hulls did crack about the second time out-repairable. That could be design, or build issue, or just bad luck. I have spent my like sailing in rugged water, and there is something to be said for a weighty designs affording a bit of durability that can lead to longevity. To wit, last year I got caught in too close between the committee boat on a start, and had to bear off, and was T-boned on the starting line (grrr!), but my Infusion was only dented (cosmetic). By contrast, some of those Acats look to be and many are, easily banged up, I don't think that a light design helps there.

yeah, there's a lot of differience between an Acat and a F18. My A is dinged up from racing and its all happened when I was just sitting around between races or when launching. My F18HT has held up pretty well and it sits on the beach full time and gets used by a couple differient people, but yes, I do agree that having a more well built hull is nice.

Mitch Booth just won the Aruba Regatta on a 2005 Tiger, sure Mitch is good but it does show how competitive well-built boats can be.

Well, I figure if a planing powerboat can go 240 miles an hour before it disintegrates -- and it does not even dig in and pitchpole -- we are doing something wrong with sailboats.

We should be able to get our center of effort and weight and power back far enough to go faster without pitchpoling.

So if the goal is SPEED, my idea is to have a fore-and-aft track for the mast, so we can move the power back as the wind increases. It's not enough to just rake the mast back farther.

Mary,

The problem with pitchpoles is related to CE height, not to fore and aft position. Powerboats have their CE just below the waterline level and its CE lever arm is small, so the torque generated is also small. Their problem is the reverse of ours: the propelller's low position actually raises the bow.

If you want more speed by means of reducing pitchpoles, it is necessary to add hull buoyancy as far forward as possible and to lower the CE height, but then, for the same area, the sail's aspect ratio is worse, so windward performance is sacrificed.

So what about hydrofoils to lift the bows? Luiz has some of those!

So I mention the "weight" word and all h3ll breaks loose? Some of you guys need to chill out some.

This is from the OP:
"I know all the F16 guys will say "make it 70 kilos lighter, and being able to sail one or two up". That's not the point here, I wanna hear propositions that can be applied to all cat designs and sizes..."

So where does my general comment not apply to all cat designs and sizes? I didn't launch an attack on the F18 specifically, and I don't even own an F16 (keep the overreactions up and just might get one though!) If the OP didn't want weight comments, he could have announced that clearly, but that would seem to indicate major prejudice, wouldn't it.
I can understand people not wanting their class destroyed by progress, but in the long run, the buck has to stop somewhere to let any real progress take place. Now hold your horses, I'm not saying we should dump F18! its hugely popular in the Netherlands and lots of my buddies are having a great time sailing their fine boats. I don't have a problem with that.
My comment about keels is that what is happening here, ie: the thinking, is very much like the way mono hull sailors reacted to cats in the beginning! What I'm saying is you can't talk about progress without considering weight, it's just not logical! Everyone needs to be honest about this AFAIC. Don't worry, I won't mention the W-word again in this discussion, it would obviously be pointless.

So I understand that this thread needs some clarification on some points.

DennisMe, stating that I did not want weight to be a parameter that can be discussed here is not the same as all hell brakes loose. It certainly was not ment as it... So let's both take a chill pill.

Of course weight is a MAJOR issue in terms of performance. The thing is that weight already has been discussed over and over again in the past on this and other forums. I wanted people to come with new design aspects that would increase performance without lowering the weight, like the designers at Hobie now are trying to do. I know it would be hard, but that's what make it interesting.

I myself sail a Taipan 5.7 which indeed is 50 kilos lighter than the F18, something that still would convince me to choose the T5.7 over a F18 if I was to buy a cat today.

I don't think that anyone would argue that the F18 class is both succesfull, and that the boats are heavy. Making things lighter would be number one on my list of things to do for all boats. Would slowly lowering the weight over 10 years, (or pick a time frame), allow the any of the classes a chance to lower the weight, while keeping older boats competitive through their usefull lives? I don't think we'll be seeing too many 40 year old F18's like we do with the H14/16. Lowering the weight slowly, year one 1 lb, year two 1.5 lbs, year three 2.5lbs, etc. Take 20-25 lbs off gradually as it becomes more viable, then start the process over. I don't think would really render anything obsolete that wouldn't follow that path in due course anyhow. As technology progress's some of the build techniques, and materials may be cost prohibitive now, but what about down the road? Ten years down the road how many of the semi serious teams will be campaigning a vintage boat anyway?

Jimi, I think a little more clarification is needed on this one. What was the original objective behind your thoughts on a 'new and better design'?

- Straightline speed?
- Manoevreability?
- Seaworthiness?
- Cost reduction?
- Control layout?
- An elitist class?
- Bigger fleet racing?
- Easy rigging?
- General crew safety?
- Sailing comfort?
- Easy righting?
- Required skill level - easier to sail or more difficult/demanding/test of skill?
- Different construction?
- Sail/rig design - layout?
- Durability?
- Weight/performance equalisation? (note: weight is only one parameter)?
- Environmental impact?

Cheshirecatman

I still remember the fight we had over the ready to sail F16 weight before we fixed it at 104kg/107kg.

I'm so glad that at that time I made the decision for these weights and stuck to it. For there is one thing I now realize to the fullest extend. There is no way to alter this weight at a later time without getting yourself in a heap of trouble and probably destroy the class at the same time.

Wouter

Great Point Cheshire..

I would add . Racing (class building/maintenace) or Sailing coupled to each of your factors.

http://en.wikipedia.org/wiki/Basalt_fiber

They must be curved or you can't lift them. And you must lift the windward foil at each tack or accept its additional (and less than useless) drag. It can work in a wide tri designed so that the windward hull will fly high, lifting the foil out of the water, but you can't avoid the extra work in a cat.

Interesting material, but put it up against R-glass, S-glass, aramid and carbon. Cost comparison?

When I was thinking about the areas people often wish to change (improve?) on cats, one particular boat stood out as being a great starting point for a development project.
It is:
- Light weight despite aluminium mast.
- One or two man.
- Easily righted
- Capable of 20kts +
- Tough, hulls will survive a hammer blow.
- Looks ripe for foil and rig development.

Anyone guess the boat?

Cheshirecatman

I think we need to define, "Light Weight" here first. Is that less than 300lbs, or less than 400, or what?

F16 = heavy!!!

So now we are talking under 200lbs? How about we talk windsurfers or kite boards then? They are both lighter and faster than any beach cat. Or are we going to discuss iceboats next?

Why digress? I'm still talking beachcat.

Cheshirecatman

I'm struggling to thing of a 2 up boat that is less than the F16 at 107kg.

didn't say if it was cheaper to produce or lighter weight than carbon fiber.... did they?

Racing was probably not a major consideration in its original design but clearly listed as a one or two man boat. Published weights have varied over several design changes.

Cheshirecatman

Low-tech materials.

Cheshirecatman

So, could I make a part (or a boat) out of this the same way I could with fiberglass or CF?

Sounds neat, although I'd need a pretty big kiln and a pile of basalt if I were to do it all myself...

It looks like it, although I cannot see any benefit. Don't however confuse basalt item with other train of thought.

Cheshirecatman

catapult

BINGO!!!!!!!!!!!

Now just think what is possible by updating the non-structural hull concept using maybe a carbon fibre spaceframe, developing the foils, maybe low pressure thermoplastic hulls to modify the hull shape.
It's just a little bit of thinking 'out of the box' many people seem stuck in.

http://www.msogphotosite.com/MSOG/pdfpage/catapult.pdf

Cheshirecatman

You can sail it 2 up?????????

Mosquito?

Hammer test?

Sport might not be raced as such but - yes! I first sailed a 'cannon' with big rig, bow foil and jib kit some 23 years ago.

Cheshirecatman

No problem

I had often thought that a neat way to do this is to make a thin wall thermoplastic hull and then pressurise it. Think about a plastic coke bottle, take the lid off and see how un-stiff it is. Then pop the lid back on and shake it up, it becomes extremely stiff.

Better still you could fill it with beer, then you would have a really desirable boat !

I wish I had the time and money to prototype one.

Gareth

Now we are making progress. Don't know how it will float but you would have fun trying.

Tell you what, you prototype it and I'll do the testing.