[copied from reply on CamBam forum]
If your hardware supports it, you might be able to do this using a custom drill script and a G84 canned cycle.
So in the drilling machine operation, set the DrillingMethod=CustomScript,
Then in the CustomScript, enter something like
G84 X$x Y$y Z$z R$r
To get the right pitch, you need to calculate the correct feedrate and spindle speed manually.
For example, if your pitch is 20 tpi, for 1 turn of the spindle, you would need to feed 1/20".
So if your spindle speed is fixed at 300rpm, your plunge feedrate would be
300/20 ipm ie 15ipm.
So in the drill mop you would set SpindleSpeed=300 and PlungeFeedrate=15.
However, for this to work your machine needs to be able synchronise your spindle and feedrates which usually means some form of feedback from the spindle.
I should also point out, I haven't tried this myself, so if anyone else sees any flaws with the above, please shout out! ...erm, and wear protective helmets/trousers and practice on a piece of foam/mdf first. Roll Eyes
Another method planned is to use a thread cutting tool and mill the threads using a spiral toolpath, which shouldn't need spindle speed / feed synchronisation. The plan is to add this over the next couple of releases.
I hope this helps.