I'm building a piano style shell for my midi controller.
Back piece with the 2 decorative flairs on it is actually on a hinge and folds down for easy access to plugging in cables.
It's made from pine 1/4" ply.
It has bent and concaved about 1/8 inch or so.
I have 1 hinge on the left side and 1 hinge on the right side. If I put a hinge in the middle, it won't fold all the way down as the bowing puts stress on the screws.
I've tried to spray some water on the concave side and put it on a flat surface with some clamps but that didn't work.
How would I go about getting this to be more straight?