There are several commonly used methods of clamping the soundboard and back as they're glued to the rims, but the technique pictured here is the one I've adopted; it works very well, and I feel no need to explore other options. I use thin bungee-cord to apply the necessary clamping force, with a caul made from masonite and cork sheet in place to distribute pressure evenly around the guitar's perimeter. The caul focuses clamping pressure on the edge of the back or soundboard, preventing any deformation of the top or back plates which the tightly stretched cord might otherwise cause. It also serves to protect the delicate soundboard wood from damage where the cord breaks sharply over its edge. I trim the top and back plates to within a few millimetres of their final dimensions prior to clamping; there's minimal overhang and therefore no leverage brought to bear by the bungee-cord on the edge of the plates.
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