foam wings

[Ian Bagshaw]

Could anybody let me know what density foam is best for wings, I'm going to have a go at making some. something I last did 35 years ago...

Thanks

Ian

[Toni Reynaud]

Just about anything you can lay your hands on!! Most of the strength come from the covering and/or a spar set in. Blue foam is denser and heavier, white polystyrene is lighter and more delicate, but I have used both quite happily. The Co 30th in my avatar is all polystyrene covered with brown paper and flew well for 5 years.

[John Emms 1]

I have made my own foam wings, and the answer is the lightest density of expanded polystyrene foam you can find. I was warned about recycled faom that could have unwanted lumps in it.

I tried bonding obechi veneer using PVA, and that takes too long to dry. I did have success with Copydex, but that leaves no time for errors. The best foam wings I have ever seen are Reichard, and they use extremely low density expanded polystyrene. The light weight balsa outer skin is bonded using lightweight glass cloth and epoxy. Clearly, the glass cloth provides the strength, and the balsa allows an excellent finish. The Reichard foam wings are no heavier than the built up wing versions.

HTH,

John

[Martyn K]

I buy 75mm wide expanded polystyrene insulation blocks from B&Q (8' x 4' I think) or 4' x 2' 50mm wide (this isn't really thick enough for a normal sized classic aerobat but I did my KFIV wings with it - just about OK), Use Gorilla Glue for skinning - applied very sparingly - as thin and as evenly as possible.

Martyn

[kc]

One pound per cubic foot is the normal aeromodelling stuff if I remember correctly. And Copydex for glue with veneer. Normally obeche veneer is used although mahogany was also used sometimes.