Yea, Ive been making gliders with foamboard type products for around 40 years myself. And, once I saw the first NAR mag ad for the M2F2, I *knew* that was going to be a clunker on a c motor - especially with standard foamboard!

Nowadays, you'll find GOBS of lighter foamy fare locally. Shoot, even the office places are selling thinner/lighter stuff than the 'old stuff'.

Now, here's what you oughta do here - make a copy of this using Adams Readiboard, obtained from Dollar Tree. You get the straightest, back of the carton sheet, and THIS is half the weight of the 'old stuff'.

As far as Depron goes, that's discontinued, or rather, no longer imported. If you can get your grubby mitts on some 1/8" of THIS, then you'd REALLY have a good sport glider. I myself have a cross between this and the Cosmos Mariner, made with Depron on a cardstock BT55 frame, that boosts and glides pretty darned well for a C motor.

Biggest issue with ANYTHING made of ANY foamboard product is warpage. *Every* single ply constructed glider WILL warp, at least some, over time. Wouldnt be suprised if your old Space Camel main sheet is affected thus.