V Twin

And while you were all arguing ...I was  sailing..........

Originally posted by G.R.F. Abuse given to Australians is legal - fact. At no time is an Englishman expected to back any comment he may have made to an Australian, the Australian should simply accept the wiser and superior words of the Englishman and be humble, in fact be happy he is even being acknowledged as anything other than a convicted felon or a bush dwelling aborigine. Don't knock my ancestors! This is the Law. So now to the facts. The factory I recently visited sits adjacent to the Bonneville Hydro electric plant on the Columbia river the electricity is free. The resin I told you of's formula is secret it is being kept in the US to protect their intellectual property from thieving Chinese (and Australians). The wood used in blank construction as well as Bamboo is from managed forests from within a 50 mile radius. The Sports that like light stuff as well as Windsurfing, which no longer has the sun filled uplands of a better tomorrow in which to bask in the fires of progressive innovation, are SUP ( a hollow race board), kite twintip and surf boards and wake boards capable of being both light yet capable of sustaining punishment in cable parks. I've no doubt that somewhere along the Gorge folk are using similar stuff to build sailboats and all manner of stuff, but those are the instances that have prompted my latests rants. You may now go to your room and reconsider your position.

Edited by Chris 249 - 07 Jun 12 at 12:17pm

I did some test samples with bamboo cloth that was being sold for organic surfboard construction.  Pretty unimpressive really.  Just a blotter to hold plenty of resin in place.  I sourced one or two other styles with similarly unimpressive results.
As a surface laminate or laminate bulker it's probably fine, but as a structural skin, it does not compete with any of the standard reinforcements.  The process of turning it into yarn and then weaving that yarn probably damages the bamboo fiber so it really is no better than cotton or hemp.  The cloth I tested was for garments,so it's really not surprising that it didn't perform well as a plastic reinforcement.  There is more to getting this right than running down to the fabric shop.
Bamboo as a structural wood has many fine qualities, but stripped up into veneer and glued together into sheet goods isn't one of the obvious choices.  A small stand will provide home grown tiller extensions and ski poles, which can be very green.
And to pile on: surface area is the biggest driver in weight. With modern materials, you quite quickly get to the limit of what can be regarded as watertight and strong enough. This is something in the order of 200 g/m^2 carbon cloth on either side of 55 kg/m^3 foam. Depending on the thickness of the foam, you can predict that the best you is about 1 kg/m^2 of surface area. This goes up as you add bulkheads , local reinforcements, trunks and everything else that takes a flat sheet and turns it into something you can use. If you want a robust boat and capable of being slammed around in waves and getting mishandled a bit,  the weight goes up.  There are advances in fibers, nano toughened resins and processing because reinforced plastics is a fast moving technology with and a dynamic market. For a long time boat building was about 10 years behind aerospace. However in the recent past, the marine industry developed techniques for building larger pre-preg composite parts than was thought possible by aerospace..... so it's possible for industrially significant developments to come from our little leisure sector.
SHC

I'd such high hope such as esteemed handbag retailer could revolution dinghy design, bad times 

I was thinking about what a similar size boat could be built down to, not looking to build a light 400.
You could lose most of the double floor.
Taking 12 sqm and adding decks etc say 20sqm times 1.5kg/sqm
30kg for a shell.
Looks like 40kg bare hull ought to be possible.
There are some kg to be lost from the ali rig.
Would it be strong enough?
Would it be going faster and hitting the water harder?
How different would it feel to sail?