On Dec 12, 10:40*am, "Steve Lusardi" wrote:
That is a bit dangerous for the tap and your work. You must have a torque release in case of bind. I use conventional hand taps
and chuck with a standard 1/2' Jacobs drill chuck on the round shank. In case of bind, the shank will slip in the chuck.
Steve

I use the drill chuck until the tap has cut enough threads to stay
straight, then switch to a hand tap wrench short enough to clear the
lathe ways or mill column.
http://www.germansupply.com/home/ima...roductid=16846
I have only 3" of quill travel and that type of wrench lets me leave
the drill chuck in place.

I've just about used up the 9 lives power-tapping, but I still back it
out with power.

jsw