[eicjon]

Hello everyone-

I am using a HAAS VF-3 lathe, attempting to drill and tap 1/2 13tpi holes in aluminum.

I am drilling the holes with a 7/16 drill, then using a G84 tap cycle to tap them. The problem is, the tap is functioning like a drill, and the end product is a hole drilled out to 0.500". We have adjusted RPMs and nothing changes.

This happens with peck tapping and standard tapping. The spindle seems to be orienting itself consistently.

We have verified the sizes and dimensions of all tools.

Has anyone else had this problem? I am generating gcode using SolidCam 2020 with a newly updated post processor.

Thanks!

[Machineit]

Post your code.

[Phishaholic]

With a 7/16 drill you will get about a 62% thread while a 27/64 will give about a 78% threads. As far as the drilling effect your spindle speed S = TPI (13) * F feed in G84 . I would suggest S260 and a feed on the G84 line of F20.0. Because 13 * 20=260. Also check to make sure you have a decimal on your feed F20. Not F20 which equals F.002 inches a minute not 20 inches a minute.