Tap Holder for the Lathe

by George Carlson

Picture of lathe tapping device

This is a drawing for the construction of the Tap Holder shown in the October Newsletter . The body of the holder is made from Aluminum. The chuck is one I removed from an old Sears 1/4" drill motor. Construction is pretty simple. The Drill Rod Shaft should be fitted to the hole that is drill and reamed in the body. I had a .376" reamer in my toolbox, this made it easy. If you don't have an oversize reamer, try sanding and polishing the drill rod until you can get a good sliding fit. The cross hole toward the front of the body is very necessary if you get a good fit. This hole relieves the air pressure when the body is slid in and out. The knurl on the body was only done about 50% deep. The body was then sanded lightly to remove burrs. When sanding, run the lathe forward and reverse to do a good job. The partial depth on the knurling is to allow a grip on the body without tearing-up your hands. If you do a good job building this device, it can work well for drilling small diameter holes. The ability to feel the cut and torque is very helpful when trying to drill a #80 hole.

To use it the device is mounted in the tailstock chuck after the hole is drilled. The handle is free to slide and rotate on the shaft held in the chuck. To use the tool, turn on the lathe and feed the tap into the work. Hand pressure controls the torque. When the tap bottoms out, release the handle and it will spin with the work. Stop the lathe, then put it in reverse. Slight hand pressure around the handle will cause the tap to back out smoothly. All done!

Drawings for Lathe Tapping Device

Small Lathe