A5fly

I have read several threads on this site about the best way to lay up a fuselage in a mold. It seems that the most common way is to lay up glass layers until one gets to a rule-of-thumb of about 8-10 oz/yd^2 For example, two 2 oz layers with a 6 oz in-between. I have tried this on a test "tube" mold I made and the part sort of feels like a soft plastic "whiffle ball" bat.

Does anyone ever use 1/16 balsa as the core similar to what is done in a wing? By my calculations, and a sample piece I made, two 2oz layers sandwiching 1/16" balsa weighs the same as would two 2oz layers and a 1.5 oz layer of glass, but is considerably stiffer than even the 2+6+2!

Has anyone tried this? I am guessing that in some parts of the fuselage it would be difficult to cut the balsa skin to shape.

SigKavalier

I have seen a similar technique but instead of balsa they used foam sandwiched in between. It was depron or zepron I believe which can be had in several different weights, and in the thin weight is plyable enough to fold a paper airplane out of.

A5fly

I worry about using foam for that purpose because it has very poor compressive strength, so the skins are likely to buckle unless heavier glass is used.

davidfee

Actually, foam works just fine for that purpose. You can easily hotwire blue/pink/grey foam into thin sheets and use that... or you can buy thin rohacell... or you can use balsa. Your pick. They all work just fine.

I wouldn't use 1-pound white bead foam though... almost no compressive strength and very uneven density.

-David