Fadal VMC 10 spindle

I have a VMC 10 that I purchased new in 1997. This machine has less than 200hrs on it and I am the only operator. It is in my hobby shop and used to fab parts for street rods and go carts. The machine sat unused for the past 2 years...

Today I did the usual maintenance, configured a small program and started to cut the parts. My S word was set at 1000. About 2min into the program the spindle started to cycle its speed and if I adjusted the pendant speed-pot to increase it the load jumped into the red. I power cycled the system and manually powered up the spindle, it came right up and held solid for 15min. As soon as I started the program and it passed the S1000 command the spindle started to cycle. I opened the rear power cabinet and (just today) realized the spindle is powered via a 10hp Baldor VFD. In any case the VFD was reading 3600-2610-3830-2200 rpms you get the jist. I power cycled the system again and restarted the spindle manually and it held fine with the VFD reading 1036+- 1rpm.

I changed the S word to 750, restarted the program and cut all 12 parts with no issues other than the VFD reading 3600 +-1rpm. Only a single green bar on the load meter.

OK so now I am stumped. Even tho S was set now at 750 the spindle sounded like 3000+ so I do not doubt the VFD's 3600 reading.

Thoughts?

test, or try a new spindle encoder first. I JUST went through this on my VMC15. I'm no expert and I have a different brand drive but I suspect it's your problem also. you'll be very happy if $300 fixes it, it is better than 3k.

search the threads for fadal spindle drive. there are several. here is mine.

http://www.practicalmachinist.com/v...control-inv0096-pooped-out-apparently-250063/

the encoder can be tested in several ways, a good one is with a multimeter. Read this!

About Fadal Encoders

I'm on it! Thank you for the prompt reply.

I did clean the encoder with a qtip, there was some crud but not much. Cold started the Fadal and noticed a message like ~ 'new component detected or memory corrupted' and still had the inconsistent S word speeds. I emailed David Caussin at VMC Electric thinking I was going to need new parts, his message back was to check the 1400 card lipo battery. I installed a new batt and the Fadal is running now with no issues.

Thank's for the feedback Pupcreek, I've had a few conversations with David deCaussin (correct spelling... I think) and he has always been helpful and willing to spend the time talking to you.

Steve