Another Angle on Flat Glue-ups
To keep panels from bowing under clamp pressure while gluing, I install lengths of angle aluminum on each end. I clamp the angle pieces just firmly enough to hold things in place. Then I tighten the pipe clamps. Unlike iron or steel, aluminum won't leave black marks where it contacts squeezed-out glue. Unlike a wooden cleat, it won't become glued to the panel.