Regarding a 1993 Fadal VMC3016 with rigid tapping:
If I have an M1 after tapping a hole to a particular depth (To blow out chips/oil), can I program to go back in a second time (deeper) and expect the machine to stay synchronized with the thread it just cut previously?
The 3 Fadals I have had would retap a hole perfectly as long as I didn't change tools. Best rigid tapping machine I have.
All my other CNCs (Matsuura, Kitamura, Haas) would open up the thread and the no-go gage would go if I programmed a second cycle on a previously tapped hole with a deeper Z depth.
Thanks, Larry - interesting about the Fadal being more precise than the others.
I didn't get an answer here soon enough, so I just went ahead and experimented. Found some peck tapping programs online, combined some ideas from different ones, and made my own changes I found to be necessary. Works great. I squirt cutting oil in the hole with a syringe from the bottom up until its full, then tap to Z-.600; M1 to blow out chips with a tube into the bottom of the hole (Z waiting at +.300) and fill the hole with oil again; "Start" and tap to Z-.850; M1 again to blow out chips and fill the next hole with oil; Etc. I found I had to add the spindle speed after every M45 and second Z depth for the program to work right - was all funky before I did that. Here's what I ended up with:
I'm too paranoid to use rigid peck tapping on my fadals. Broke a tap in very expensive part so i don't do that anymore. But good to hear about Larry's results.
Warrenb, setting up and testing your RT is quite easy. You only need a rigid tapping test tool (SVT-0077- $75 in stock), put in a collet holder and run a short rigid tapping program while you have an indicator in the threads watching for deviation. You should be able to adjust Gain and Ramp in the parameters until you get it tight as you need. We have a video on our web site showing how to do this. I also have a test Rigid tapping program I can send you for the test and adjustment.
Let me know how or if I can help.
FadalCNC Support