I'm new, I want to build a mini trimaran

[upchurchmr]

Tiny,

Very nice looking work.

I notice you are reefed on the main, when do you need to do that - windspeed? Since you reefed the main only was that for control/ balance issues?

The last photo seems to have the bow very high, with the angle of the boom I would have expected it to be depressed, was that just a wave or something?

How long have you been sailing this boat? Are you happy with the fixed seating? On my previous catamaran the seating position was very critical for performance and prevention of bow burrying. Are you concerned with the fixed positions?

It appears that Solways have relatively reduced sail area - are you happy with what you have?

Sorry for so many ?????, but I don't see any tris in my area to talk about. And I would like to build something but I'm previously use to much more and higher sail area. So I just wonder what I would accept with my advancing age and belt size.

Beautiful job, Thanks.

Marc

[Tiny Turnip]

Doug, Marc, thanks for your kind words. I would hasten to add that it is not my design, or build, but Solway Dory's; I was considering a similar build, and was going to approaching Solway Dory for drawings, but they had this for sale. It is specifically designed as a two person camping cruiser for beach hopping off the West coast of Scotland. I bought it in July this year, and have had a blissful month sailing it several times a day, from the isle of Gigha. I have to say I am delighted with the boat; it is so well mannered it almost sails itself. The balance of the mizzen makes it particularly easy to sail, I think. Rigs are modest, and unstayed, and reef by rolling around the mast. I have had it at 12 knots, (and surfing, goose winged, at 9.) Word has it that its sister boat has achieved 17 knots, but I consider I have reached the limit when I’m submersing the leeward outrigger. I’m not interested in capsizing or breaking it! The modest rig sizing means a capsize is very unlikely, and it should be rightable by sinking the stern.
Marc, on this outing yes, I reefed because of the windspeed, and only reefed the main partly out of laziness, and partly because leaving the full mizzen would give a bit of weather helm, which I thought was no bad thing in gusty conditions – a tendency to point up and spill some wind. In that final picture, I think that is probably what is happening; the leeward outrigger is well under, and I suspect I’m having a momentary buttock clench! We’re probably hitting a little chop too, and for some reason it looks like I haven’t got the leeboard down. I have never experienced the slightest tendency to bury; by contrast my Dart 18 based pedal boat buries merrily in big waves. Conditions on the lakes (we’re on Coniston here) can be interesting; the wind funnels and gusts, changes direction around the mountains, and there’s a decent fetch.
The boat is very tolerant of loading, a bit clattery with just one up, and no gear, but I like that. The seats do slide- in fact they are just loose fitted.
Quite happy with the amount of sail. It’s a very, very confidence inducing boat. I don’t like my sailing to be scary!
It seems to me to be a very well considered (here comes the controversial word) compromise, properly balancing the different performance characteristics to meet the brief. I have wondered how the boat would be both with more sail area, and with more carrying/ sleep aboard capacity, and if I am thinking about tweaks towards both opposite ends of the spectrum at the same time, I guess it indicates it is a good compromise for a little cruising tri.

[upchurchmr]

Tiny,

Thanks for the comments, I showed the post to a coworker who was a Hobie sailor and he seems interested in the general class of boat.

Marc

[Petros]

You might consider building using skin-on-frame. It is very cost effective and very light. I have built some 12 or 13 small boats using skin-on-frame, including a trimaran. If you can find a low cost source of suitable fabric (cotton, nylon, or polyester can all work, anything with a fine tight weave), the hull should cost about $50 to build. If you can salvage the lumber it will save even more. I found a left over roll of upholstery fabric for only $4 to use as a skin.

A friend of mine and I built a skin-on-frame trimaran in about 12 hours (including the sail, mast and rigging) for a sailboat building contest. We bought 1x2 for stringers, used plywood frames, glue and screwed it together and than stapled on the fabric skin, covered it with latex paint we got for free. It was 18 feet long, main hull width was about 18", had two outriggers about 4 feet long each. Total cost of materials for our boat was about $50, and we only used about 5 lbs worth of tools(mostly hand tools) too. If you have access to a table saw you can rip down your own stringers from a larger plank, it would save some money.

You can see a picture of it here;

http://katyapalladina.zenfolio.com/p684685668/e45ee4a9

I would use one of the sails you have, and just design the boat around it. A smaller sail will work fine, it will be easier to handle and not get you into trouble if the wind picks up.

Good luck, have fun with it.

[oldsailor7]

Arthur Pivers "Frolic" trimaran is a simple and cheap Tri to build and has a remarkable and safe performance. Plans are obtainable from here:-
The Mariner's Museum in Newport News, VA acquired
all of Piver's collection when Piver disappeared, years
ago. They do sell his plans.

www.mariner.org
100 Museum Drive
Newport News, VA 23606
(757) 591-5124

Library/plans link:
http://www.mariner.org/library/plans-drawings

[Willzilla]

I've been away and I'm going on holiday for four days tomorrow.

The Solway Dory looks amazing! I won't be forgetting that for future!

Petros, I'm liking that a lot its what I reckon I should be doing (skin on frame construction) for now. I'm excited because it will be cheaper, lighter and I can make the boat bigger! I'm still not sure if proa or tri and I like both but after looking at proa's I don't even think a tri would be needed. I would like to have a nice net to lie on and with a tri then it wouldnt look right with only a net on one side!

either way I'm wondering If I could have the opti sail up front and my kayak sail at the back. I don't see any problems? Also if I had leeboards at the front and back that pivot on a bolt, could I put one up slightly to change the center of leeboard-ness (is there a word for that? sideways resistance?) for the center of all the sail area? From what I seen I just assumed the proa's with 2 leeboards was set up like that for shunting? I'm not sure why. I would like to build a boat that could shunt, but maybe just not have it set up to shunt all the time.

Also I have a rip saw and access to a table saw if I have a design worked out I could get cut all the bits of wood in a better shop then our current garage set up we are working on. Then take it home to build! I could get some fabric from somewhere, thats not a problem. It would be cool to use dacron but I have no idea where to find it. And if I could afford it too I'm not sure if it would be worth it.

I like the idea of building around the sail(s) I have

Anyway thats it for now and if I don't reply to anyone tomorrow morning then I will in 4 days when I get back.

edit: Ive just been doodling. Here is what I would want to do with a proa, but the sails arent to scale and are a bit small.

Also I did some drawings for a real mini tri that I kind of started this whole thread over, but I drew this here because i had the idea of having the hammock on it XD which i think is awesome and would be super fun on a nice day and relaxing. It uses the kayak sail I have. The great thing is that with skin-on-frame I could pretty much start building that tri right away and almost not spend anything on it! I have the wood ( I would just use pine for now unless I found something else like oregon lying around) I dont care if it doesnt work after a few years because I would be learning a lot and could make a better one if I really still wanted it. It could be a kind of test project for now. Then maybe I could work on a proa or a bigger tri. I'm excited about this skin-on-frame because it opens way more doors for me.



Tell me what you think. I'm interested to see what people think of the mini tri. Its shifting the thread way more onto topic from what I've been looking at.

[upchurchmr]

Willzilla,

If you do a tri, don't make a wide main hull. There is no reason since the stability is in the combination of hulls, not the wide main. You are not going to have enough power to really plane witht the sails you talk about. The narrow hulls reduce the drag so much that you will do very well without thinking about planing. Find something like a Hobie 18 hull shape with a transom. Even a 24" wide kayak is more width than you probably need, but that would be an easy size. Make the bow/ freeboard higher than a kayak. leave an open footwell between the crossbeams, but beef up the sides significantly to make sure it does not break in the middle. Take a look at this site: http://gaboats.com/ the designer has passed on, but his wife sells the plans. There is nothing directly matching a trimaran needs, just the ideas.

George Dyson in the US sells Dacron cloth, cheap (but you would have shipping issues) others have used dacron used from covering aircraft wings. I'll try to find the information I got from Dyson. He no longer has a web site.

Marc

[Petros]

There is lots of information about skin-on-frame construction on the internet, just go find it. I would not recommend using two sails on your first build. KISS-Keep It Simple Stupid!

The easier to build, the faster you will get on the water, the less it costs, and the less trouble you will have controlling it on the water.

A tri with one dagger board, one rudder, one mast and one sail is going to be simple and easier to build and control. Or even going to a monohull.

Here is a skin on frame dingy that used almost all salvaged materials and cost less than $40 in materials to build, is 14' LoA x 4' 8" beam. Uses tough plastic sheet for a skin (materials used to winterize boats-heat shrink makes a nice hull):



at first launch:

[ancient kayaker]

Here's a web site on skinning; do a web search on Dacron and Nylon and other skin materials, the have different characteristics, so you can select the one that suits you.

http://capefalconkayak.com/howtoskinakayak.html

[Tiny Turnip]

skin on frame is a good idea.

For reference, I lammed together this 15ft, 14"wide ply outrigger canoe with a mate for a raft race for our kids a couple of years ago. It only took a couple of days, but we had no time to scavenge materials (on our little holiday island) so it uses mostly new, only 4mm ply, but I still think, IIRC, that it cost the best part of $100 in materials.
camping kid build for raft race
pictures towards the end of the thread.

[JRD]

Willzilla, there is a little trimaran called Pivaka, designed and built by its owner in Australian Amateur Boatbuilding magazine - Issue 74 July/Aug Sept 2011

It is 2.4m long built from ply and as an experimental lateen rig based on pacific island craft. Im not sure if you can get access to back issues but it looks afordable to build and has quite simple build methods.

[oldsailor7]

Duck Flats wooden Boats.
John Marples 3M Trimaran.
Plans , kit or complete boat.
http://www.duckflatwoodenboats.com/m...ery.php?KID=55