I intend to make 3 curved rafters for a garden application. Each rafter
needs to be 7ft(L) x4inch(H) x 1-1/2inch(W) finished. The radius of the
curve will be 10ft.

Material will be 1/4 inch external grade ply laminated to make up the width,
glued and screwed over a former. How much "spring back" should I allow for?

I had Resourcinol in my head but a previous post suggests this is OTT for
this sort of application (probably mega expensive too), suggestions
welcome.

I can probably buy these, but then thats just another learning opportunity
lost.

Best Regards

Steve