Looking for someone to service a nineties Hurco BMC-20

[southernmenace]

I have a nineties BMC-20 that I am having a serious problem with. I gues it is only really "serious" since it is my first week in business for myself, and the parts that I have promised my first good customer are looking like they wont get done. Not a good way to start things off.

The spindle was making a knocking/rattling sound. Sounded like a nut or something bouncing around inside the motor. Got really bad when RPM were over 1000. Knucklehead that I am, I disassembled the entire motor, cleaned it out (didn't find anything either) and put it back together. Now it wont even turn on. When I turn the spindle on, it spins really slowly for about five seconds, then it faults out. "spindle fault check drive?" something similar to that. It looked as if someone had been in that motor before as well.

Can anybody help me out with this. Does anyone know where I could find a good serviceman to check out this machine? It seems like everytime I try to fix anything on my equipment myself, it turns into a three week game of trial and error. I really dont have time for that right now, and would prefer to hire someone that knows what they are doing.

 

[Nordic]

Hi there

It sounds to me like your spindle bearings are gone and it might also have damage your motor.
BE SURE THAT YOUR MACHINE IS TURNED OFF AND HAS BEEN OFF FOR AT LEAST 5MIN check with a Volt meter.
Masure the ohm.on you motor(is supose to be the same on all u v and w (humm... maybe its diff. on us motors), and if it is short to ground, masure the cable also.
If the cable and motor are ok.
Check also Ohm. on your NCU and your PLC

try to take the spindle apart and replace the bearings (prop. lined bearings) so be sure to put them togather as they should.
Take pic. and wright memos on what you do.
ps. sorry about my spelling.
best of luck
Valdimar

 

[GBeaman]

One thing you might look at too....
We had an old hurco making terrible spindle noises. Disassembled expecting to redo bearings and found that there was a large love-joy type coupler on the shaft of the motor driving the spindle. Well it broke in half and was rattling around inside the air cylinder housing. I forget what it cost but it wasn't too bad. Our hurco guy usually stays in Texas and is usually way busy, but he is great! He is independent and has worked for hurco for about 20+ years. He might be able to help you over the phone. Ken Borgmeyer is his name and his phone # is 817-360-3097 He is more then familiar with your machine. Hope something helps. Take care.
-Greg

 

[Milacron]

To add to the confusion, bad spindle/motor noises are sometimes not mechanical or electrical but electronic...in the spindle drive ! Had a Bridgeport VMC with Siemens drive years ago that sounded horrible like bearings gone or short but problem turned out to be the spindle drive !

 

[Roooster]

If the encoder disc has been put back on the shaft in the wrong place, you are done up like a kipper. It needs to be marked before pulling it off the shaft and put back in the exact same position.

 

[GBeaman]

Depending on the year make and model it may not have an encoder. I think around 95 the encoder and rigid tap came in. If older then it probably doesn't have an encoder. Just my .001 cents

 

[southernmenace]

I am done up like a kipper! Whatever that is!!

I didnt mark the encoder, and I believe that it is my problem. It seems the only way to get it resolved, is to pull the entire motor off again, and ship it to Yaskawa. Seems like a waste, just to have someone orient the encoder.

Any ideas? Yaskawa field service?

Buddy over at The Hurco Store says that the sound I was hearing was more than likely the belt, and could have been remedied with some WD-40. He is probably right, and now I have shot myself in the foot, and caused myself far more problems than I could have imagined.

 

[BLMac]

Talk to Anton at precisionzone.com and see if he can walk you through alingning the encoder, if not he will fix it much cheaper than yaskawa will.

 

[Milacron]

I didnt mark the encoder, and I believe that it is my problem. It seems the only way to get it resolved, is to pull the entire motor off again, and ship it to Yaskawa. Seems like a waste, just to have someone orient the encoder.

Nah...don't ship it...aligning the encoder is easy once you know the proceedure for that specific machine. Someone at Hurco should be able to fax you a sheet on the proceedure...or maybe the info is already buried in the maintenance manual somewhere.

 

[Mark McGrath]

As Don mentions Siemens ac servos can sound as though they are disintegrating mechanically with an electrical fault.I have one on the spindle of a Chiron and the N card in the 610 drive went and what a racket this thing made.If you lost the encoder position you have probably lost the commutation.
I know where on the net there is a good explanation of how to set the encoder up again but the name of that forum is not welcomed here.
The guy who posted the "how to" for encoder setup was Al the man.

 

[southernmenace]

Hurco will not help out with anything that has to do with the motor. I talked to a field tech today, and he said that Yaskawa wont even ship a new encoder to Hurco! Of course Yaskawa won't guide me through the steps of aligning the encoder, claiming that it is "proprietary information".

There appears to be a crack in one of the resistors in the encoder circuit board, and I want to have it checked out by someone that knows what they are doing.

I am bringing to a place called REA Technologies, right outside Charlotte. Anybody ever dealt with them?

 

[Milacron]

Hurco will not help out with anything that has to do with the motor. I talked to a field tech today, and he said that Yaskawa wont even ship a new encoder to Hurco! Of course Yaskawa won't guide me through the steps of aligning the encoder, claiming that it is "proprietary information".

That sounds odd as it doesn't square with my Hurco experiences. In fact I owned a 1996 Hurco BMC 20 just 7 months ago and had some trouble with a couple of axis overshooting home postion.. and one of the techs at the Hurco main office faxed or emailed me a few sheets on how to adjust/align the encoders.

So either they have got snobby in the last few months or you got the wrong guy.

Having said that I sometimes wonder if some of these companies treat customers differently depending on how they perceive your experience level. What I mean by that is if you seem clueless they may be more reluctant to help as they figure they'll end up spending too much time with you and perhaps they even worry you may end up screwing up stuff even worse and blaming it on them ! But if they perceive you are experienced and know what's what they are more willing to help as they figure it will be a more 'slam bam thank you ma'am' situation.

Just a theory of course....but that's how I would be if I was a tech support guy...it would be torture trying to tell someone how to do this or that if they just barely knew what they were doing....esp if "the boss" was breathing down your neck and you had ten other phone calls backing up. But it would be a joy to instruct someone that knew what was what.

 

[Roooster]

It's the encoder inside the motor that's been taken off the shaft. These things aren't keyed, have no markings and are just an aluminium disc with a layer of magnetic media around the outside edge. Hurco don't have any access to Yaskawa setups for these. I changed an encoder body (not the disc) a few years back and have re-bearinged a few motors but have always marked the disc.

 

[Milacron]

Hurco don't have any access to Yaskawa setups for these.

Well they sure as hell do for the Yaskawa axis servos/encoders...so why not the spindle motor/encoder ?

That really makes no sense, esp considering Hurco themselves would have needed this info when they built the darn machines in the first place !

 

[Roooster]

The motor is a complete finished unit that is mounted on a plate and fitted to the machine. There is no setup on the motor itself as the orient was a magnetic sensor mounted at the spindle. If the motor was replaced, the only set-up was zero offset for the signal voltage. The encoder sent signals to the drive and the drive output the encoder pulses to the control.

 

[Roooster]

Sorry to double post. The axis drives had setups that were followed to set the V/RPM, zero offset. The same applies to the axis motors as to the spindle motors. They were sealed, out of the box onto the machine with no fiddling with encoders. Some of the 90's machines had leadscrew mounted encoders but these weren't connected to the drives they went straight to the control.

 

[southernmenace]

Just got back from REA Technologies, which is near Hickory NC, not Charlotte as I previosly posted. It took them quite a while to repair the busted up circuit board, and reset the encoder, but they had it up and running, and claim that it is fixed. I am going to install it here in a few minutes, and see if it works. Cost me $1275. Still makes me cringe, but I guess its not bad considering they got right on it.

Like I said earlier Milacron, Yaskawa will not ship an encoder for these motors to Hurco. That came straight from the mouth of two different Hurco servicemen. REA said that Yaskawa will not send one to them either.

 

[Milacron]

Just got back from REA Technologies, which is near Hickory NC, not Charlotte as I previosly posted. It took them quite a while to repair the busted up circuit board, and reset the encoder, but they had it up and running, and claim that it is fixed.

Just out of curiosity, how did you go from a resistor with a crack in it, to a "busted up circuit board" ? (i.e. from something very minor to what sounds major)

Anyhoo sure hope the root of the problem was electronic as I initially speculated. But if it turns out it sure enough was the belt, don't be too embarrassed to come back here and tell us as you know we all secretly like to hear stories like that so we won't feel so bad about all the times we did similar clusterforks

 

[kwmkoester]

don't leave us hanging!!

So what happened with the Hurco spindle? I've read the whole thread and am on the edge of my seat with anticipation! Was it the "busted up board"? WD-40 on the belt? Encoder position error? Tell us, please!?

 

[Derekadams]

So what happened with the Hurco spindle? I've read the whole thread and am on the edge of my seat with anticipation! Was it the "busted up board"? WD-40 on the belt? Encoder position error? Tell us, please!?

$3.50
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