[dizzypistons]

Hey all,
I have a doozy...
We have a machine that does various operations and whatnot. One of the operations is rigid tapping.
Here's the facts:
1. We can run a 3/4-16 tap with no issue. 3/4-20 is alway oversized by about 0.004". We don't run any other sizes.
2. We trammed the face of the turret, indicated our pockets and tools in, etc.
3. Did a bar cut test, everything looks good (spindle and turrent seem to be aligned).
4. Our pre-tap hole is good, and we tried moving it around, with no success.
5. We are using a tension-compression floating tap holder.
6. Here is the portion of the program:
N09(3/4-20 TAP T#-3392)
M98P1000 (offset program for touching off)
M8
M26
M6
G0G99G97X0T909
G0X0Z.4
M29S400
G84Z-.5F.050
G80
M9
G0Z2.0

Anybody ever hear of anything like this?

Thanks for any feedback!

[timlkallam]

Have you checked the H limit on the tap
If youre in g95 mode your code is correct
If in g94 the feed should be F20