The replacement keys were made with balsa wood, topped with 3/32 inch maple, that I cut to that thickness from a larger piece. I cut the maple top
layer to the exact size of the key, then glued it to the balsa wood bottom which I deliberately made slightly oversized. After the glue set, I sanded the
bottom wood layer until it matched the maple top layer. This ensured a smooth surface. Cutting the balsa wood the exact size would have left it rough,
and would also leave no margin for error. Next I need to seal the wood and attempt to closely match the color of the existing keys.