Hello,
This is my first post on this forum. We are tapping a hole with an 1 3/8-6 Tap. Some of the taps we have overload the spindle on my machine, and others seem to work. Does anyone have a formula that will help me figure out the spindle HP required to tap this hole? We are going over 4" deep. Right now I am sometimes able to do it on a 20HP Haas machine.
Thank you in advance.