So I had this job I had to make some internal 1/8 - 27 NPT threads. I've threadmilled normal threads before but not NPT threads. I bought a multi flute thread mill with the taper already in the tool and modeled the tool to the manufacturing specs in Mastercam.
So I went to the Machinery's Handbook, and E1 (Handtight Engagement 0.3736), is the size that I modeled the hole diameter as in Mastercam. I did not override mahor or minor diameter calculated thinking that since the thread mill already has the taper in the tool, Mastercam would adjust automatically. As well as depth. If I change the depth, I assume Mastercam will adjust the toolpath to adjust for taper to hit the sized hole that I modeled.
Drilled with a Q drill. Cycle start. And it barely touched the walls. So I started slowly increasing the diameter with my wear offset and I ended at like -.04 when I hit my right size.
So my question is, did I mess something up in Mastercam? Am I using the wrong size hole in Mastercam? Nothing in the Handbook is even close to what the diameter would be .3736 + .04 = ~.414 The closest thing to that number is the outside diameter of pipe D which is .405
So I went to the Machinery's Handbook, and E1 (Handtight Engagement 0.3736), is the size that I modeled the hole diameter as in Mastercam. I did not override mahor or minor diameter calculated thinking that since the thread mill already has the taper in the tool, Mastercam would adjust automatically. As well as depth. If I change the depth, I assume Mastercam will adjust the toolpath to adjust for taper to hit the sized hole that I modeled.
Drilled with a Q drill. Cycle start. And it barely touched the walls. So I started slowly increasing the diameter with my wear offset and I ended at like -.04 when I hit my right size.
So my question is, did I mess something up in Mastercam? Am I using the wrong size hole in Mastercam? Nothing in the Handbook is even close to what the diameter would be .3736 + .04 = ~.414 The closest thing to that number is the outside diameter of pipe D which is .405