5/16x36 tap source

Make it.

Ted

Grand Tool Supply

Their phone number is (800) 922-0512........

Dave

Randal O'Brian wrote:

Hey Ted,

Am I seeing correctly that you have the tool on the backside and upside down to the work? That means the lathe is running backwards and you'll be traveling toward the tail stock, right? Nice job on making that tap. I haven't tried it yet. Still trying to perfect my single point tool technique.

Bernd

Indeed you are! The Smithy chuck is held to the registration surfaces by three bolts so does not have the problem of coming loose when running backwards. I do not have or use a thread gage since I cut metric threads as often as SAE. Also, I like to thread away from the unthreaded portion or shoulder of the work piece to avoid having to stop just so. I let the cut run off the end of the work piece, move the tool clear with the cross slide, run back to start, advance the tool and cut again.

Harold points out that the rake is ~6 degrees only at the edge and decreases as you move in on the flutes. I'm certain he's correct but the tap cut at least as well as any I have so I assume this is a minor point for hand tapping.

Ted