Zenair CH601HD

[phaxtris]

Ahh I did think about making sections, and although it's fairly symmetrical to the eye I'm sure it's not perfect. If I were to do it with pourable foam I would have at least made some kind of cardboard sections/dams to keep it under control, using the spray foam wasn't difficult to build up, aside from the bottom, pesky gravity.

I'll look into the bendable foam, I was thinking of building some 'walls' on the inside of the mold, just wasn't sure what to use to form it, the foam sounds like it might be the trick I need.
I don't think it needs a massive amount of re-enforcement, but I think it should be stiffer, around the split, maybe one or two walls/bendy foam strips on the big spans. I obviously don't want to add a whole pile of weight so I will add a few re-enforcements and see, add more as I feel necessary.

As for the side work on home builds, I don't think I would make a cowl for someone, but I wouldn't mind getting into some of the welding, I've seen some of the welding out there on home builds and I see room there

 

[LenVW]

We used ‘polyurethane foam insulation’ on some applications to muffle noise.
Probably would not stand up to hot areas in the engine compartment, but, the foam has good structural properties for stiffening purposes.
One neighbour has used it to reinforce his GLIDER segments.

 

[StevSmar]

Oh boy, I’m so jealous. You’re living my dream of building a home built aircraft.

I no longer have my license and am unlikely going to get it back- and building an aircraft that I’m not going to fly doesn’t have the same allure.

 

[PeterT]

Divinycell is one of the common composite sandwich core materials. It comes in sheet form which you can cut or shape or heat form, 3 PCF density so quite light. I've also seen it pre scored with kind of a mesh backing so it can conform to curved surfaces. Last-A-Foam is more of a structural foam, increasing densities & better heat capability. Man prices are getting crazy. For reinforcing 'stringers' on 3D surfaces another technique is to slip woven cloth socks over shaped foam cores, resin saturate & then cure that on the surface (usually vac-bagging technique). The strength is in the composite tube, the foam core is just along for the ride.

Foam | Aircraft Spruce Canada

Aircraft Spruce Canada is a worldwide distributor of certified and homebuilt aircraft supplies.

www.aircraftspruce.ca

But if you really want to melt a credit card then look no further than Rohacell. used in aviation, race cars, all that good stuff. Oh and high end RC models. The cores are CNC milled, then get placed into CNC milled molds with CF skin & spars etc. kind of a reverse process. So even the paint layer is directly on the mold. Gram savings & strength costs exponential $$. Fuselage components have no core but use an expandable bladder from the inside pressing CF outward to the mold.