Alternative to marvelous Buccaneer 24

[Gary Baigent]

The B24 has created huge interest among multihull people wanting a decently fast, simple and inexpensive trimaran design with enough accommodation for 2-3 people and capable of coastal sailing/racing for a few days or so. Obviously Lock Crowther hit the spot dead centre - but I think another 24-25 foot design could be achieved with more speed, similar accommodation and most importantly, no more expense to build .... so I'm starting off doing it, basing it on my fantasy sort of C Class trimaran efforts, (apologies to those who have seen this before) but with the option of different rigs, wing masts of course but of varying chord dimensions: 1/4er 1/3rd, 1/2 and full wing; the 2 latter rigs for day sailing/racing (or overnight in settled weather) - and rigs that can be lowered a la BMW-O. This sounds complicated and a hassle - but with careful thought, it can be achieved; boats will have to be on the dry to achieve this. And yes, yes, sounds extreme but look at the crap going on with the Australians wanting a more modern rig on the NZ boxy 8.5's. Also I'm talking about 2 moderate wing mast versions too - just leaving the options open.
Build will be 4mm tensioned ply with laminates of glass and carbon, numbers of bulkheads and ring frames. This boat will be light and strong - but it will be light without outasight high technology expense. I'm starting on the material expenses for the hull and beam right now.
Comments/criticisms welcomed?

[Doug Lord]

It's going to be gorgeus and very fast-good luck and go for it....

[bruceb]

Gary, I like my Buc 24, but I would not build one today-there are enough changes that I would want that I might as well start with a clean sheet of paper. I really don't care what it looks like, but try not to loose the simple function of the Buc type boat. AND! Please make it fold! The rest is up to you- 25'-27' seems like a good size. Bruce

[Gary Baigent]

hi Bruce, Simple function is my middle name, but folding a 25 foot beam is .... somewhat tricky. It could be achieved, maybe, with a configuration that Randy Smythe has done on his scissor tri. The floats would also have to pivot - and it all sounds NOT a simple process. But it would allow for the boat to be shifted as one unit, and not unlike Farriers, in a way. Then another alternative is dismantle beam and floats for trailering ... but I don't like the idea of fastenings to hold the platform together - and you people in the US seem to have an aversion to pulling things apart and then putting them back together. Actually, it is probably universal.. So round in circles you go. We are spoiled in this country with numerous sailing areas and bays for moorings; at 25 feet wide you can forget about marinas, so I lean towards an unmovable unit, epoxied, glassed and carbon-ed together to make one strong platform. The Farriers are very, very clever, but the folding mechanism makes them a bit too heavy, for me. Anyway, point taken, I'll chip away on it, make two versions, one fixed, one scissor.

[DarthCluin]

I love the shape of the hull, but if I'm reading the lines right, its only about 40 cm wide at the gunwales (not counting the flat flared area). What sort of accommodations are you proposing?

[Gary Baigent]

400mm, that's a house Darth. No, you're right, I'll spread the gunwales another100mm. The cabin behind the airfoil beam will be extended a little too and that's where a couple of bunks will be fitted, maybe even sleeping across the boat. But no mistake, this will be a bit like a bayonet trench from WW1, don't expect salubrious accommodation. Actually not much difference to the bunks on a B24. There will be another bunk below the shallow cockpit. The priorities are that the boat has to light, fast and inexpensive - and accommodation is just shelter, camping really.

[bruceb]

What sort of displacement are you expecting? Two skinny bunks are fine as long as there is some sitting head room. I know folding/dismounting will probably compromise the simplicity, but in the US, it is just necessary. We don't have the open space that you do Bruce

[bruceb]

What sort of displacement are you expecting? Two skinny bunks are fine as long as there is some sitting head room, camping style is ok. Also, how does a long shallow hull like this tack? I know folding/dismounting will probably compromise the simplicity, but in the USA, it is just necessary. We don't have the open space that you do Bruce

[Gary Baigent]

hi Bruce, I'll be disappointed if I can't build it to weigh less than 400kgs. On the point of skinny bunks, there will only be one in the cabin, sleeping crosswise next to the beam, the other is under the cockpit and possibly a third fold down one just forward of the beam - in that real fat area. Goes without saying it'll be claustrophobic .... but you can't have everything - as Dick Newick said, or words to that affect.
Tacking is tricky on very light tris but there will be a high aspect ratio daggerboard set to one side and coming up through the cabin, and it should pivot okay on that. I have no trouble with Groucho Marx - which is similar, just larger. You can see the GM'sdagger lying on the port trampoline in the jpeg. I'll post some more detailed drawings soon. And I'm really taking note on what you experts are saying. Cheers.

[Gary Baigent]

Here's the folding/scissoring setup. The cabin swivels with the beam, bit like a tank's gun platform, on a flat base that will be difficult to seal (if I go for conventional headroom) from flying spray and excessive speed. It would be easier to keep the cabin a low module just high enough for a bunk- but that sounds a fraction extreme. The three cylindrical bearings, especially the big central one will require some careful building - it will be set on and through the "gun turret" base and onto carbon reinforced ring frames and struts - and when the scissor position is out and the platform ready to sail, the beam and floats will have to be locked with struts and large pins, don't want it folding while doing 40 knots, eh?.

[bruceb]

That is very ambitious. How much do you estimate the beam and floats will weigh? I might be happy just lifting them off. B

[Gary Baigent]

Bruce, as a rough indication, shooting off the top of my head, G. Marx's big beam, 11 metres long and built in stripped plank paulownia with glass and carbon sheathing, could be easily picked up by the two of us and we estimated around 75-80 kgs. Then when it was on the boat it was wrapped with more carbon fibre in the mid section - so say 90 kgs. The floats were light at 20 kgs each. On the proposed scissor foiler I'll be aiming for half of that total weight of 130 kgs - beam is smaller section and chord, only 7.62 metres long, and smaller floats.
Here's a revised version of the main hull, wider at deck level.

[jamez]

Originally Posted by Gary Baigent

Here's the folding/scissoring setup. The cabin swivels with the beam, bit like a tank's gun platform, on a flat base that will be difficult to seal (if I go for conventional headroom) from flying spray and excessive speed. It would be easier to keep the cabin a low module just high enough for a bunk- but that sounds a fraction extreme. The three cylindrical bearings, especially the big central one will require some careful building - it will be set on and through the "gun turret" base and onto carbon reinforced ring frames and struts - and when the scissor position is out and the platform ready to sail, the beam and floats will have to be locked with struts and large pins, don't want it folding while doing 40 knots, eh?.

Hay Gary,

Good to see you're picking up on this again. The floats are what maybe 2.5 meters long? How about making the crossbeam a little longer than LOA then you could swivel it 90 degrees with the floats going past the ends of the main hull. The floats could then be fixed.

[Gary Baigent]

hi Greg, How's your cat coming along? Yes I did think of that - but thought trailering the scissored thing would be tricky enough as it is, meaning a very long tow rod. and the amas across the trailer might look very strange on the highway, plus the fixed foils would foul trailer and vehicle too. I would prefer it moored and stuck together solid - but Bruce and others, and the Aussies, are adamant that boats be trailerable. But nothing is set in concrete/epoxy and I'll do some oversquare drawing versions - certainly would reduce complexity having the amas fixed. Here's the general concept ... with two conservative wing masts:500mm and I metre chord versions.

[bruceb]

Gary, it does need to come apart, but at those weights, it would be just fine bolting? things together. I would think two people could easily carry and assemble the floats and beam. My Buc's floats are 200+ lbs each- too big to handle easily plus my rig is heavy and complex. Light and simple should make a big difference. Bruce