Rossiter Pintail Mortagne sur Gironde, near Bordeaux |
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Laser 28 - Excellent example of this great design Hamble le rice |
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List classes of boat for sale |
Plywood Kit Designers |
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Noah ![]() Really should get out more ![]() Joined: 29 Dec 04 Location: United Kingdom Online Status: Offline Posts: 611 |
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Not sure what the contender reference is intended to mean, but the wooden boats are cold moulded, aren't they - not ply. AFAIK Signore Bonezzi(?) in Italy still builds beautiful hulls but I bet they are eye-wateringly expensive.
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Nick
D-Zero 316 |
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JimC ![]() Really should get out more ![]() ![]() Joined: 17 May 04 Location: United Kingdom Online Status: Online Posts: 6662 |
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With judgement, skill and appropriate use of brute force you can get a fair amount of 3 dimensional curvature in ply, and even more if you build the required area from two layers of thin ply rather than one layer of thick. Back in the day it was even by no means unknown to cold mould a small area where extreme 3D curvature was required and do the rest of the boat in ply.
But the shape of a Phantom, with large flat panels means that foam sandwich with better panel stiffness is going to be superior, and there's really no way round that. One only has to look at the way the Phantom PY plummmeted once foam sandwich hulls and carbon spars were widespread in the fleet. However you can get too excited about boat speed if one is not a front of fleet sailor. Is it really more fun to be racing for 10th place rather than 15th? I suggest that if you are out on the water enjoying competitive sailing with congenial people then the job is done. |
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KazRob ![]() Far too distracted from work ![]() ![]() Joined: 22 Oct 16 Location: Scotland Online Status: Offline Posts: 245 |
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+1 from me on that sentiment
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OK 2249
D-1 138 |
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mongrel ![]() Far too distracted from work ![]() Joined: 27 Aug 08 Online Status: Offline Posts: 304 |
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Wooden Bonezzis’ were plywood, still very sought after, as quick/quicker than the FRPs’.
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maxibuddah ![]() Really should get out more ![]() ![]() Joined: 06 Mar 09 Location: United Kingdom Online Status: Offline Posts: 1760 |
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most of the reason why the PY plummetted was down to the epoxy boats being up to 14 kgs lighter than the GRP and even more on some wooden boats. The carbon spars did not make that much difference in the earlier days other than perhaps the helms not being knocked so much.
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Everything I say is my opinion, honest
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Riv ![]() Far too distracted from work ![]() Joined: 23 Nov 13 Location: South Devon Online Status: Offline Posts: 353 |
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So, fast for most boats is stiff panels and high resistance to twisting assuming optimum weight and weight distribution
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Mistral Div II prototype board, Original Windsurfer, Hornet built'74.
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JimC ![]() Really should get out more ![]() ![]() Joined: 17 May 04 Location: United Kingdom Online Status: Online Posts: 6662 |
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Doesn't explain why similar PY changes have been seen on just about every other class that's adopted foam sandwich. |
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Cirrus ![]() Really should get out more ![]() Joined: 29 Oct 15 Location: UK Online Status: Offline Posts: 590 |
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....all epoxy Phantoms hulls come from a mould taken of a wooden boat. Not from the mouth of one of the 'developers' of the Phantom epoxy hulls I have spoken with on the subject ! .... besides don't believe me just put a rigid steel rule across a epoxy modern hull and see for yourself.... They did not all come from a mythical single ancestor without some subtle but still significant ... eer 'tweaking' along the way !! Why would you not tweak the plug and tooling to real competitive advantage when the set tolerence rules allowed a medium sized bus to be driven through them and you were changing materials anyway (and therefore also changing the limitations imposed by the materials involved). You can bend ply and you can also twist it but if you effectively get into cold moulding it, as has already been said, it is not really regular plywood anymore and that really is the only way to get a compound curve into a multi-layer wood shape ... And frankly if it was even practical in a formal production sense it would still be more efficient to build in foam and epoxy imo if allowed - so why do it ? And as goes with the Phantom you can add many other classes to the same list of those suitable to be 'tweaked' when a switch to moulding went through - Solo, Fireball, Enterprise etc spring immediately to mind and you will think of others I'm sure (though lets agree maybe not as completely with the OK maybe !)
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tink ![]() Really should get out more ![]() Joined: 23 Jan 16 Location: North Hants Online Status: Offline Posts: 789 |
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Interesting stuff, the classic theory is that ply can be bent into a conic form (this has been stretched slightly to tortured or compound bending). Draw two diverging lines on a piece of paper, bend it normal to axis of symmetry of the two lines and it easy to see what ply is capable of. Jump 50+ years ahead and two things have changed: fast hull shapes are very different and we have CAD that could create a stiff multiple panel (not necessarily chines) hull shapes made of stiff conical ply forms.
All very hypothetical as development cost would out weigh the number of people prepared to take the risk and spend the time actually building the resulting boat. All a UK perspective though, lively home built Proa scene in Poland because it the most boat you get from the least materials.
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Tink
https://tinkboats.com http://proasail.blogspot.com |
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Noah ![]() Really should get out more ![]() Joined: 29 Dec 04 Location: United Kingdom Online Status: Offline Posts: 611 |
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Well I never knew that. Always thought they were built from summat exotic. I stand corrected.
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Nick
D-Zero 316 |
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