[ArsenalProducts]

I've scoured the threads related to rigid tapping and can't seem to find any help on the issue I'm currently having.

I have an early 90's Kiwa 510 Colt with a Fanuc OM-C controller. Over the past few months I have had intermittent problems with the rigid tapping. Sometimes I repeat the program and it works. Other times I bang my head, change code, change tool offsets and it won't work for several hours and then it does start working. It is not working now. The machine does definitely does have rigid tapping enabled and I I just tapped 5000 holes for one project last month with no issues. I'm repeating the same job, same code, and now it will not rigid tap.

There are 2 different things that seem to occur. First - Sometimes the spindle never ramps up to the specified RPM (or ramps very, very slowly). In this case it just seems to sit there and never enters the tapping cycle. I assume because it doesn't hit the specified RPM. Second - and the most common, which is happening right now is that it looks it immediately ramps up to full speed (far past the specified tapping RPM in the program) and immediately errors out. The error that usually pops up is: 430 Servo Alarm : Z Axis Error. On occasion it also pops up a 431 error and yesterday it was popping up a 433 error.

I have scoured the parameters to see if something has changed from my known working parameter backup file. I have the Rigid Tap Troubleshooting for Excel 510 Colt document from John at Shoprag but unfortunately I'm not sure where/how to dive into the spindle board and orientation board adjustments in that document. I've also attempted to test the parameters as suggested in that document but the machine typically stops as soon as the spindle kicks on so the diagnostic parameter isn't particularly useful yet.

Does anyone have any suggestions on next steps to go from here? In the meantime we'll be using a floating tap collet but I would prefer to get the rigid tap up and working properly.

Thanks in advance!

[jancollc]

It sounds like encoding. How is the spindle encoder driven?

When my VF2 stopped tapping it was the encoder belt. Easy fix.

[ArsenalProducts]

The spindle encoder is belt driven off the back side of the spindle. The belt is intact. Someone else has suggested that it could be the encoder itself. I'm not proficient enough with the electronics to know how to check the encoder itself. Any ideas?

[landslide1]

check the spindle servo drive parameters F-31 rigid tapping =1. my 0m use to sit and wait eraticaly when F31 wasn't set.