Centering an Insert in a Turned Knob
I’m making knobs for a tool cabinet, and I want to put a small decorative insert in the center of each one. How do I do that?
L. Clift, Albany, NY
First, turn a short length of ebony or walnut to a thin cylinder. A finished diameter of 1/8 in. to 11/64 in. works for most knobs, but choose a size that’s well proportioned for the knobs you plan.
Chuck a knob in the lathe and put a small dimple in the face with the point of a skew chisel. This will ensure that the hole you drill for the insert will be dead center.
Measure the diameter of the ebony cylinder and select a drill bit that’s a hair smaller. Use a drill chuck in the tailstock of the lathe to hold the bit. Finally, chamfer the cylinder you’ve turned, so it slips easily into the hole…