The RAZOR

Folks,
For some time I have been thinking about designing and building a chined F16.
I figure that it is about time I did something about it.
So I have finally started.
The craft will be built much like you would build a chined Kayak.
I will be adding photos to an albumn on catsailor as the work progresses.

If it all goes to plan it should be a pretty easy and quick boat to build.

Only scarfing pics there right now but I hope over the next couple of weeks things should start to take shape. Actually to make it even easier the scarfing could be replaced by butt lap joints allowing all parts to be CNC cut.
Anyhow I will try to tear myself away from some of my other pastimes and see how things progress.

Regards,
Phill

Blade, Taipan, Stealth, Viper and now the RAZOR which I presume will be the "easy build but still good performance" F16. Things are good!
We also have one-offs like the boat Ncik did (if it is F16 compliant and sailed as an F16, I dont know for sure?), Altered and the rumours of two other designs coming as well (one from Europe/Germany(?)) and one from a well known marine architect and member of CS.

With so many designs to choose from, both from manufacturers and building plans, the biggest issue now is having parts like masts and beams shipped around the globe.


Phill, way to go! Eagerly waiting for more news about the RAZOR build, and not the least, how it sails when it is done!

PS: Phill, any renderings to show us how you envision the hullshape?

maybe next year's winter project for me?

Stitch and Glue?

Like here:

http://pygmyboats.com/Construction.htm

Eric,
Similar but in may ways simpler.
The idea is something that is quick and easy to build.
So only 4 panels plus deck and a minimum number of bulkheads.
No jigs just a stand to hold the hull upright while the parts are assembled. I showed the drawings to a friend today and he is keen to build a 14ft version. Didn't do any work on it today. Went sailing instead. We got 11.5 knots out of a 29ft full bridge deck cruising cat that sleeps 8 going upwind. Damn good for a cruiser and good fun.

Tomorrow I will cut out the panels for the hulls.

Regards,
Phill

I had a spare hour today after shopping with the other half so I cut out the keel panels. With the side panels also cut out I just need to glue the gunwales on and I can start assembling the hulls.
I may get a chance to glue them on after work tomorrow.

Just have to see.

I'm interested in a smaller cat for my kids. Nothing available here really suits--in fact, I sold my Hobie 14 turbo because I just hated it and it was still very heavy for my kids. Building a light 14 footer for them is an option; keep us apprised.

Eric,
The idea behind a 14ft version would be not only quick and easy but cheap. I may even end up building a 14ft for myself.
If you are really interested we can talk off line about your preferences for such a craft.
My staple gun was playing up today so only glued the gunwales and stringer for two hull sides. Took one hour each when it should have been half that.
I don't get any more time until Thursday. I think I'll do the other two sides then and then go watch the A class worlds.

I got my brother's wedding Friday, sailing saturday and bike riding sunday and back at work Monday. Bugger- need more days in the week.
Anyhow I'll try to fit in a bit here and there and may even take some more pics over the next week.

Regards,
Phill

Phill and others,




Over the last months, while playing about with landyachts, I again renewed my desire for a simple small catamaran with a unstayed rig. Just a single sail craft that is easily fully assembled and disassmebled. I'm convinced that a market is to be found for such a craft if its hulls look pleasing enough. Both for kids and adults alike. I too would love to own such a craft fro the small spare hours that I'll be getting in the next years. Not having complex systems like a spi or trap are actually benefits in this concept.

Anyway, take this thought as a general reply not as say advice or anything.

Best of luck !

Wouter

My mate and I have been building a foiling moth design of his over the holidays. Flat-pack cnc-ed carbon and foam sandwich panels put together in a female mdf jig, with the inside joins taped and frames and bulkheads installed in about 3 hours. Started a week ago and he is fairing the external hull join tapes today, with plenty of mountain biking, missed days and sleeping-in breaking up the build. I estimate about 40 man hours of build time.

Only items left to install are the wand push-rod guide tube and foredeck, should be water-tight and maybe launched by the end of the week, assuming some small parts have been ordered. All other parts are complete from another boat.

The hull build is extremely quick with this method and produces so little dust and fumes. Will definitely consider it, or a modification of this method, for future builds. Maybe flat panel sides and frames with a moulded bottom. There are some big boats being done this way.

Glass or carbon versions of your hull could be popular.

Ncik, could you build up two of those moths, join them together and have a foiling cat?

Wouter,
A 14ft version will essentially be a single sail craft although may have a hooter option.
Hooter as opposed to spinnaker for easy of rigging and the ability to use upwind in light air.

The hulls seem pleasing enouh to the eye on my PC. I expect the real life one to also look good.
However with the amount of sail area I'd want to put on a 14ft version it won't have an unstayed rig.

I hope to take some pics of progress on Thursday or Friday.

Ncik,
I'm beginning to realise how quick this build would be if the parts were CNC cut and it is quite surprising.
I have a friend nearby building a CNC machine. I'll have to get on his case and get him to finish it before a 14ft version is built.

Regards,
Phill

Timbo, it could be done, but easy enough to design dedicated cat hulls. The time consuming to build, or expensive to buy, part is the foils, more than the hulls now-days. And I'm not convinced T-foils are quicker on cats. L'hydroptere dihedral style is the way to go, simpler all-round and probably faster too.

Only problem with CNC is that the larger machines are rarer. We were lucky that the moth fit perfectly on ATL's standard panels and cutter. Larger hulls would require scarfing, but ATL have a system for that too.

any more pics anywhere of the hulls/concept?

Gero,
The design I'm building can use a butt strap joint instead of a scarf joint. The butt strap is used in the kayaks and 14ft Paper Tiger quite well. I used a scarf joint because I've done heaps of them but someone who is not confident with that type of joint would not have to use it.
The machine being built here is 2500mm long so it could probably make a kit quite easily and that would have a butt strap joint. Just to keep it simple.

Patrick,
I will keep taking pics as the project progresses and I will do a write up on the objectives of the design. Got a lot of family stuff on right now so can only grab an hour here and there but I will try to keep it moving forward.

http://perverted-moth.blogspot.com/

any update?

Eric,
I have not been near the Razor for a week or two and it will most likely be another two weeks before I get back to it.
The last week and next two weeks are going to be very hectic.
But in two weeks time I will again have some time for the Razor.
When I get a chance I will try to take a couple of pics of where I'm at.

Regards,
Phill

Phill-
Don't forget to get some sailing in too!! About the joints- What about utilizing a "step" as in the hydroplane floats, speedboats and some cats at the joint? If you had a bulkhead there it would be even easier if you wanted a significant step, ie more than just the thickness of the hull material.

Kirt

Kirt,
Good point.
I just gave up two weeks of sailing and took a week off work to build a 40 metre retaining wall with a fence on top and then paint the front verandah.
The wall and fence are a segment of an circle with a 60m radius just to complicate things a little more.
All good fun.
When all this is done I will progress the RAZOR AND get some sailing in.
Regards,
Phill

Ah yes!! "Honey-Does"! I know them well! They have often gotten in the way of my sailing as well! I'm in the middle of putting together a 40x54 ft building- hopefully then I'll have a nice spot to build another boat- Perhaps a RAZOR?? But I did take 2 hours yesterday to get out on the Taipan at least!

Take care!
Kirt

Folks,
I have been sidelined for around a month now meeting some very important family obligations. Most of those have now been taken care of so I can get back to the RAZOR.
So far I've put in probably around 12 hours and I need to start assembling the hulls. Had the panels been CNC cut I think so far around 3 hours of my time would have been taken up. Just what is needed to glue on the gunwales and sub-deck stringer and mark in the position of bulkheads etc.
I'll try to get some more pics up either today or tomorrow.

Regards,
Phill

The hull panels need a stringer.
To stop the staple gun from bruising the timber I cut up an ice cream container which is the burgundy bits of plastic that you can see.

This shows the panels required to make up the skin of the hull.

RAZOR looks sharp

You actually stapled the stringer on to the panels to let the glue set?

Rolf,
The answer is yes and I also stapled the gunwales on too.
I didn't bother with the plastic on the gunwale staples because that will have a layer of glass tape over it.

Regards,
Phill

I got up at 6 so I could get my ride in before the heat .
On the plus side it gave me a couple hours to work on the RAZOR. So I added some pics to the album.

Regards,
Phill

Phil,

Now I understand. You meant to design and build the RAZOR first then design and build the BLADE.
This thread could go on forever.


Thanks for the progressive images.

Regards,

Peter

Peter,
As far as this thread going on forever!

I may be a bit slow when I build- but not that slow.

More pics added to the albumn.

Phill, great picts. thanks for keeping us updated on you project. In the last picture where the hull halves are being joined up, could you post a picture of the underside of the hull? I am interested in the way you shape them, is there a cutout piece, like an outside bulkhead, to hold the shape? And are the two narrow strips across the bottom stitched to the side panels, like a stitch and glue kayak?

Also, on a completely unrelated topic, our media finally picked up on your wild fires, awful picture, 130+ dead, etc. My thoughts and prayers are with you all down there, I hope you get some rain soon, they did mention it was flooding in the north but no relief down south.

Tim,
There are 4 frames made from scrap timber. These are used to sit the panels in while they are wired together. The frames are not the shape of the hull but they are designed to make sure the panels join at the correct angle for the intended shape which is formed later when the bulkheads and subdeck are added.
It looks very box like right now but hopefully that will change.
It is stitch and glue like building a kayak.I think the photos you are asking about are in the catsailor photo albumn
and the link below should take you there.
http://www.catsailor.com/gallery/index.php?cat=10302

Let me know if they don't cover what you want to see.
***
The fires are bad news.
The people of NSW and Vic are all hoping for rain. Victoria is in flames and will be for weeks- already it is the worst natural disaster in the countries history in Victoria.

On the other hand the people in Queensland want the rain to stop- with record 12 metres of flood waters in places.

Regards,
Phill

Ahh yes, those are great pictures and answer most of my questions, worth well more than 1,000 words! Now, are the hulls fully symetric, as in, you build port/starboard exactly like the other, or is there a separate port/starbord hull and frame set? It looks symetric in the photos but I wasn't sure.

I really need to clean out my garage, get rid of all the kid's old bikes, trikes, etc. and start a project like this, but I think (since I already have a Blade) I would like to try a 20' trimaran. Build the center hull only, and use old Inter 20 hulls for the amas and rig/sails.

Tim,
They are symetrical.
You could always dig up a set of plans for a Farrier Trailer Tri 680 (22ft) and just build the centre hull or better still build the lot. The amas on those were a very simple shape and would be pretty simple to build. I have a friend with a 720 and he and his family get a lot of use from it. Although his later designs are much faster. Having a boat that you can sleep on and rig in 20 mins would be a great family boat. I know you have a lake house so the rigging may not be an issue but it may open up other options.

Regards,
Phill

Phil,

I am fascinated with what one can do with stitch and glue.

Some question...

why did you butt strap the bottom panels after stitching instead of scarphing them before?

why is this a faster method to build than the standard Blade method?

or are you just expecting better speed because of the chines?


regards

xuraax (currently building my own version of the Blade)

xuraax,
The Razor is about simplifying the building and the butt strap joint is simpler than the scarf. The keel panels are flat and do not need a scarf joint. In hindsight I think the side panels will take a butt strap joint too. The curve will not be that great and the joint can probably be made of after curve is induced.
Along the same lines the chines are easier than steaming the hull to coach the ply to take the intended shape. This design is much less stressful for both the builder and the ply.

Regards,
Phill

i actually did not need to steam the panels to coax them to bend. What I did was to bend the hulls as far as I dared and then left the wood to settle into the new shape for some hours. then i squeezed some more.

Thank you so much for designing this! As soon as I get out of grad. school and resume having a "real" income, I'm building one. By the way, I vote for butt joints all the way! They're so easy.

I built two stitch-and-glue boats from Bateau.com, and I've been incredibly impressed with that method. I don't have the patience or attention to detail required for tortured ply, but stitch and glue is right up my alley.

Folks,
I've not touched the Razor since February.
I've been busy with outside home improvements.
But since it has been raining so much lately I thought I'd take the opportunity to get back to it. So I put a couple more pics into my albumn. Just some shots of the keel glassed. It starts to give a bit of an idea of the under water shape.

Regards,
Phill

Phill,

it will be interesting to see your approach for putting the sides on, or are they already in place? Pretty hard to tell much from the picture really, but it do look kind of flat

Folks,
I shelved the RAZOR project for quite a while. Just too many other projects going so it has been sitting in my workshop gathering dust.
A few weeks back I decided to get back to it.
I undercoated the hulls today.

The building has been fun. Really just like the 2 CLC 18 kayaks I built a few years back.


Regards,
Phill

Photos or it didn't happen!

It used to be easy to add photos now it is a pain in the butt!
I'll see what I can do.

Razor Hull1

Razor Hull2

Razor Hull3

Hobie might love you but I don't.

Phil- Right click your photo on Flickr, select properties, then highlight and copy the address. Put the address between this: [img] **address goes here** [/img]

That's nice. I DO like those bows Phill!

How flat is the run aft?

John,
It's one thing to design something on a computer screen but quite another to build it and see it unfold in the flesh.
One of the joys that I will never tire of when prototyping designs.
I'm quite excited by what I'm seeing in real life and it will be great to see the Razor in full flight. I've sent you some pics. If you want any others just let me know.
I'll post some more pics once the hulls have some proper paint on them.

Regards,
Phill

Hi Phill
Congratulations. Those hulls look extremely impressive and can't wait to see more photo's.
I just 1.5 questions;
What are the main design differences between the Blade and Razor and what are the major construction differences when building in Ply.

Mark,
Was that 1 or 5 questions?

This is a chined version of the second generation hull shape.

It is considerabley more bouyant than the earlier Blade shape particularly forward of the front beam.
The relatively flat bottoms of the hull are now converted to chines.
This should deliver even more dynamic lift off the breese. The additional fore/aft stability will allow the crew to trim upwind for min drag and the sharper bows will slice very efficiently through the chop. There is no steaming required to achieve this shape and very little fairing so building can be from either ply or foam glass sandwich. The insides construction has been significantly simplified. It is no harder than building a pair of kayaks. I found it all just good fun. But I like this type of stuff.
Regards,
Phill

Brilliant Phill, I had feared never seeing the Razor build but I'm very happen to see otherwise. I feel this design is an excellent development.

Well done indeed, looks good.

Wouter

Phil,

do you see this method being useful for building to the 8.5M class or bigger using thicker ply?

regards

What many forget is ply was the most advanced high tech solution, (and with the correct skills, still is), up till the Kiwi's (Jennifer Julian) started using cores in glass boats.. The US & Europe were at that time using solid glass boats or cold molding.. The impoverished kiwis and Aussies builders could not afford the expensive materials of resin and glass. er But what they did have is many learnt the trade of building Aussie and kiwi WW2 planes. And good supplies of quality ply.


If you look around there are pages and pages of historical documents of well build offshore races built out of ply.. So the answer.. is yes a 8.5 meter cat could be built from ply if the builder has a good skill set and ply is available.. Its no longer as available as in the 70s and quality has become an issue as well..

Like Stewart says!
Apart from basic skills the biggest problem would be getting good quality ply. The stuff coming out of China may not be so good but there is a French company still making the good stuff. You really would be better off getting BS1088 quality ply. Read the specs and check the ply yourself to make sure it conforms before buying.
Alternatively you could use the same method and build from foam sandwich.
Good luck.

Don't mean to thread hijack but ply 8.5s are still being built, from reading the forums at crew.org.nz a ply boat 'atttude' is one of the fastest and lightest.

You don't fancy designing an 8.5 Phill, I hear there is some interest in Oz!

An 8.5 would be fun.

I need no convincing that good ply is still a good way to build boats. I own a self build Micro and despite the fact that it is now 15 years old it requires very little maintenance.

The reason I wrote earlier is that I would like to build a larger more modern design but I would prefer to avoid double diagonal or strip building.

Indeed I do know about the efforts in NZ and am particularly impressed with "Attitude" which I understand is built from stressed ply.

Unfortunately I could find very little info about their building methods on the WWW so if Phil decides to take on the project I would very likely be interested.

Regards

http://perverted-moth.blogspot.com/

basically a ply construction, but with carbon foam sandwich panels instead.

There was a boat here (think she is in Sydney? now) called wings. a 36'foot stressed ply river racer.. Basically a ply 18' skiff with the wings stretched to 36'. Very quick..
The only issue with ply is compound curves..