Catamaran beam construction

Well, I was originally not planning on doing the beams- so glad I reconsidered...... this was the rear beam.

 

If that much glass and resin were done in epoxy; that wood never wudda rotted

 

I was going to say with that much glass and resin the wood is barely relevant !

 

love the thoughts- FYI- the picture is a cut through right at the end where it was mounted to the hull- the glass you are looking at was what was used to attach it to the hull. FYI-I am trying to figure out what wood was used. We normally use mahogany

 

Looks like a close grained hardwood from here. Mahogany put up wet would rot like that on the inside or if the resin were polyester and not sealed.

Main thing is to avoid putting it up wet and full encapsulation..

 

There isn’t any rule of thumb guidance for that can be given for this kind of thing. You have to actually calculate the strength and stiffness of the wood structure and design the composite piece to replace it.
My understanding is that Dick Gibbs was a hack and butchered some pretty good designs by using the cheapest materials and sleaziest techniques. Your dedication to the Shark design is the only thing that has preserved the crap he sold.
I think that doing a careful job building the wood beams is likely the best option. Wood is actually a pretty good material for the design, and Rod was no dummy.
SHC

 

Well, it would really help me if you could be clearer on your feeling towards Gibbs....... I haven't rebuilt any of his boats- I'm working on a set of English hulls now, and next in line is Linda Rogers boat, a wooden one that was the inspiration for (her recently deceased )husband John to build the series of Cedar Sharks.
I have taken apart a few Gibbs boats for the hardware. They are heavy.
Rob