Just use a piece of sandpaper, double it up and sand the surfaces round. Put the hinges in the middle, and when you are ready to cover,. seal the hinge joint with your covering. As long as the surfaces are free to move, it is not that big of a deal whether you have 30 40 or 26 degrees of bevel. What is important, is that you seal the surfaces- Just cover it regularly and fly it, then seal the surfaces and fly it you WILL notice a big difference.

Jetts