Small Tri's under 20', any mention of foils is banned..

One could argue that wooden windmills were incredibly inefficient and that the latest all singing and dancing carbon bladed turbines are actually not much better.

 

Lets talk about boats please.

 

Ummm ok,

I say goody! I've got a big Woody!!! And it's still stiff! Unlike a plastic skiff!

 

And that was the point of my question, at about 20ft there is a crossover of good and bad points for both plastic and wood. Expense on one hand, poor ability to get good designed curves with wood. Ease of build with foam and budget prices with wood.

Please don't compare though commercially built Lasers and the likes, built from polyester resins and cheap glass to the later boats such as the A Class catamarans where Epoxy and carbon is used extensively, many of the early Boyer boats are still around as stiff as first built some 15 years ago.

For just a few dollars more in the build stage, those Lasers wouldn't go soft and need replacing every few years. I think that was one of the major gripes when the Cats were excluded from the Olympics on a cost basis. If you took a Laser campaign of 4 years changing two hulls each year, it actually was more expensive than the Marstrom built Tornados which typically lasted 2 full Olympic cycles of 4 years before they were deemed to need changing. Just a better built and designed structure using better materials.

 

I am still designing my 19ft all curves foam sandwich trimaran. Nothing has happened on it for a few weeks as I have had a lot of other drawing work to do.

The Strike 20 trimaran, Zest 14ft racing dinghy, Jazz 30 powercat, Sailish 28 budget race catamaran. At least one of each set of plans has been sold, so there is some urgency about finishing the plans! All are built in plywood. But once they are finished (getting close now) I'll be back on the new 19fter, still unnamed.

It seems everyone is drawing the same sort of boat, so next year should be an interesting one. I would love a day racing trimaran, but must sell at least one of my existing boats first

BTW I am in San Francisco right now and will be going out on a F27 later today hoping to see the AC boats sailing. Then on Sunday, I'll be out again, this time on a Multi23 trimaran. Interesting stuff this R and D but someone has to do it!

The big cost in Laser sailing is not the hulls but the rigs. You really need a new sail for every regatta. Most top sailors buy 6 sails a year

Richard Woods of Woods Designs

www.sailingcatamarans.com

 

Solway - Osprey trimaran

Solway have quite a nice trimaran - though they class it more as an outigger canoe. See below link. Pretty boat, and I like the idea of a cat ketch rig for it given the narrow hull, though I am sure this is not the most efficient rig for a boat this size. Definitely had an influence on what I am trying to build. Looks nice for transporting. Anyway worth a look for those who have not seen it.


http://www.solwaydory.co.uk/products/sailing-canoes/osprey-outrigger-sailing-canoe/

 

Pulse 600 sailing review by Richard Ward of Seawind/Corsair. A few changes mentioned including slightly increased dihedral a solid strut folding system to be fitted replacing the synthetic waterstay and a bowsprit/prodder to be added.

http://sail.corsairmarine.com/sailing-review-on-the-pulse-600

 

Pulse 600

Increasing the dihedral is a great idea-good decision. Since they're going to change the folding system the new angle could probably be incorporated in the new system. I like the bowsprit as well.

 

I can sort of understand no video on the first sail (smart phone?), but no hand held gps?

the sailing video they do have is a bit too "arty" to be of much use to those wanting to study how it sails

agree with sprit and dihedral changes

lets hope they soon sail and video it against a Sprint so we all have a known benchmark to compare it to

RW

 

I basically agree with everything you say, foam is good. Particularly resale, but that assumes you want to resell the boat, which is one of the things that makes boat building super unappealing to so many people. The decision to make a boat, or make one you can resell, probably doubles the cost and time to build (geography dependant to some extent). And here we are talking about a development class that strangely despite everything has not developed, but we are suggesting methods that seem set to keep the class in a box for ever. If you look at stuff like CLC, despite all the advantages mentioned, not a single foam boat in the fleet. They actually offered a kit for a Proa (all the gasbags on the proa forums are so in love with), for under 4K, 30 footer. Where are all the corecell fleet kits.

At the high tech end we have Strings that Meade built, and it had developed plywood hulls with carbon skins, not sure why, but that was the choice, very experienced guy. Knowing the numbers of the hull of Adrenaline, I can guess. The Gs actually built hulls that won races against all comers, in ply for cheap, and the normal response was to ban their boats, which is part of the reason cats are "so fast".

Boats need to be built somewhere, and pal up the road built a SUP, and even though I lent him my hot wire saw, and he sliced off thirty percent of the bulk, the neighbours for literally 100 yards downwind were still pulling bits of foam out of their lawns a year later. Nice stuff. It should be pointed out that you can order, carbon and 1088, and it all arrives next day no hassle either. And then a few days later your hull is done. You can proto at a cost that makes time spent on this thread seem steep.

Splinter actually is the boat many are taking about as never having been, in this thread. And speaking of banned words, is quite possibly the only type of boat that would beat a balls to the walls, all carbon, #####, and wasted time super project, in a 20 foot tri. Presumably only in light conditions. But where else can you own light conditions, for well under a dollar a square foot of skin.

The only other thing I would say about foam vs wood is, why? Kurt has been on this for a long time, why can't you combine the best of both. Well one reason is the extemists who want to spend 100 hours per square foot won't allow it, and for another, it is hard enough to find people who can build in either. And further, it is harder still to find people who know when to use either to best advantage. But it is not always the case that every boat is better in one or the other material.

 

Those just aren't true. Wood is faster or the same, to the same finish standards (there is not bright finish equivalent to wood for foam, and if one treats wood purely structurally it is as fast or faster than foam). The poor ability to get designed curves isn't true either, most of those foam curves are molded over wood forms, and you can do the same curves in strip. There isn't any equivalent process in foam to Stressform, there is KSS, which is all great, but not for the most part an ideal curves format. KSS's big advantages are speed of closing in space, arguably surface finish, and the fact the end result is foam, whereas with tortured the end result is normally wood.

Something like a rounded bow, is probably more freely shaped in foam, but a fair line may be more freely shaped in wood. Not entirely irrelevant is that wood can function effectively as both a tensile and compression material, and is available in a lot more variations.
th

 

What's a Sprint?

 

I'm not knocking wood at all, it has been proven time and time again by those interested in wood construction to be a great product.

But lets look at probably the best and most long term user of both wood and composites. Gliders are arguably the most developed of all aerodynamic and lifting surfaces. They began building in wood, went over to metals and Ali skins and ended up with composites. Theres has been a long road of development and ended where they are for a number of compelling reasons.

But there are people out there who just love wood construction, it does give a feel that composites doesn't whilst building and I think for a 20 foot Tri at the sort of weights we are talking about in the T20 thread, is a practical alternative.

 

New guy here !

I am currently undergoing my 1st build, a very simple canoe to see if I enjoy the process and want to build something bigger. So far so good.

My ideal boat would be raced ( very casually, against PHRF boats, results will mean nothing ).

Day sailing, I'm not a cleat it off and putz around guy. Sailing fast. Would need reefing ability though, so I could slow it up.

I am near the ICW and it links up into largish sheltered sounds and rivers. Seaworthyness is not a huge priority, I could go for miles and miles in basically flat water.

Camp cruising, unlikely to be more than 1 night at a time. If I go for longer it would be singlehanded Everglades challenge style hate mission.

Interior wise I would like a single inside berth, mainly for when I drink too much at the sailing club. Overnights with company and off the dock would probably be a boom tent or maybe a tent on the beach.

Intention would be to keep the boat on a mooring, although a relatively easy transition to a trailer would be good. If I realised life meant I couldn't sail for a month or so, I would rather take it home.

Modern, fast looks are also important, the Strike 18 just doesn't quite do it for me. The Strike 20 might very well. You can call me a fashion victim, but I don't want to pour that much time, effort and money into something I don't find sexy.

One thing I haven't read about much in this thread is build time and cost. I understand that beach cat hulls might be a compromise, but for me the time saved by not having to build AMA's could be significant. Same with intricate folding systems and being able to use the rig and sails off the boat the hulls came from. I think if most of the parts can come off one donor boat there are less chance of unexpected costs.

It sounds odd but I want to build, and as much as like the idea of the more complex boats, I am looking at the quickest easiest build possible, it will still take a long time.

From everything I have seen so far, the Strike 20 seems to be closest to perfect for me.

I have one question, the design brief calls for F18 or Tornado hulls and rigs. These are expensive boats. It seems to me that some older designs are similar in size and sail area. How much difference would it make if a NACRA 5.8 / Prindle 19 or even a Hobie 18 or similar were used as the donor. Looks like it might make a approx $3,000 worth of difference ?

Also, does anyone know any details or have pics of any Strike 20's in existence of being built. All I have seen are basic line drawings.

 

Be a little careful on your selection of donor hulls, yes the older boats may seem at first cheaper but they have some drawbacks.

The Prindle 19 is certainly on my radar as its basically a copy of a Tornado but with narrower beam, the Hobie 18 is definately not, its heavy, has very heavy components and an even heavier mast, all the things you want to keep, where as the Prindle has relatively light components and mast, but heavy weight hulls which are 1.5 ft longer, with bigger sails.

The other thing to consider is shape, the later the boat, the better and more suited the foward bias of bouyancy of the later hulls, to cope with the more and more flat spinnys, the F18's are nor using ( virtually genoas in disguise ).

Another consideration is if the T20Trimaran class gets underway then almost certainly a late F18 is the way forward. Also a late F18 such as a I have bought ( Capricorn ) cost only about £ 1500 more than a much older Diam that was advertised locally. That 1500 extra gave me a nearly new main, spinny and jib that was on the later boat, plus it had a trailer plus good launching wheels. That Capricorn with its shape and sail package will make a very good donor boat but at a bit more initial cost, a cost almost certainly I would have had to buy within the first year or so.

That sexy modern shape is not here yet but as I've said before, there are at least two designs about to be released which are very modern in looks, they are not far away.