Trimming
Then the ebony head is sanded on the disk sander until the pencil line disappears. I use a shop made squaring jig that rides in the miter slot of the 12" disk sander. This jig must be a perfect 90 degrees to the sanding disk because nothing looks worse than keytops that are out of square – even by a little bit. Then I check the width at the bottom and top of the ebony with a digital caliper that reads in 1000ths of an inch. If the readings are within 3 thousandths of an inch I consider the head to be square – if not, it’s back to the sander. Finally, I check for square with a small combination square. The same process is done for the tails.
