Posted by: Ken Smith on June 26, 2005 at 21:03:07:
In Reply to: Re: Skins and floor posted by Geoff Sobering on June 23, 2005 at 13:06:23:
Geoff:
Gougeon brothers used this material or similar in some boats built in 1970's. I bought a boat made about 1978 with these plans, and the bottom of the cockpit was soft. Some load had colapsed (crushed) the honeycomb. There are boats out there made with foam of various types in the void between the cockpit floor and bottom. I sailed a Polish boat that use 10mm klegecell there. Rules interpertations are a litle fuzzy here, as I recall. The rules call for hull materials as wood with figberglass reinforcing as optional. No foam meets this spec. Now the argument is that there are wood listings, to meet the hull spece, and the voids are filled with the foams (or hexcel) as a non-structural material. (Herrumph!) In the 1980's the argument was that the paper was wood fiber, so legal. But the paper is nomex, a man made fiber. There is also plastic hexcel and aluminum hexcel materials and carbon hexcel cores, and end grain bulsa, and others... A high volume of solvent is necessary for good structural strength, and good contact is necessary -- usually vaccuum bagging.
I do not believe that a technical committee question is on the record in this regard. So the technical legality is questionable. On the other hand, lots of boats have some portion of this area filled with foam. I have such a hull.
IMHO, usuing anything other than wood listings is excess expense for no gain in performance and no reduction in weight. In an existing boat, it cannot be easily removed. In a new boat, there is no reason to add it.
Besides, Geoff, haven't you got enough on your hands to figure out with the new renegade?
Ken
DN4137