foam sandwich for ribs and stringer?

General Discussion
1

has anybody used foam sandwich for ribs and stringer. its super strong and weighs nothing. or is foam a 4 letter word around here?

what about 1/8 th ply glassed both sides? i want something strong and light cos my first board came out too heavy.

also, my thoughts go out to all the californians affected by the massive fires raging over there at the moment. as an australian i know the horrors all too well.

good luck from all your aussie friends…

sean…

2

Oneula started some Boo-xps sandwich ribs.He stopped posting on Sways before it was finished.Danny Hess may use foam for ribs?Paul uses thin ply with glass-carbon.Many ways to hold up the skins.

I am planing on using some XPS foam scraps to make some ribs on a ply hollow(woodish)board.

If you want to go light just make a COMPSAND.Use 1lb foam and 1/16 balsa sandwich skins and wood rails=super light.

Have fun,

3

you could try this

4

Danny Hess makes hollow wood boards using regular EPS for his ribs. The stringer is on the rails, cork/wood ply a la Jensen.

5

sorry i did not relise you were talking h w s

hope everyone is all right

6

I just used 1/8th doorskin for everything, ribs, stringer and deck. it seems solid, but I havent ridden it yet. The outside is glassed with 8 oz though, no glass inside at all. Its not that heavy, or light. Easy to cut everything with a hand saw. This is my first try though, so dont take my words as advice.

7

A good friend of mine, that builds composite aircraft, uses PVC foam (Divinycell) to form the ribs (1 inch wide) in the wings to which a fiberglass skin is attached. The FAA inspectors really liked the system. Should work fine for HWS.