Need help on a scary problem....

[kentsui]

Two days ago one of my guys threw the switch on our 4020 and the Z ran straight down and hit the table, broke a tool, ejected some clamping..you know ..scared the crap out of everyone in the shop, that kind morning.

I came in about 20 minutes later and instantly noticed the head of machine in the bad-mojo position with the workers pointing at it like a baby who's head had spun around about four times ala Linda Blair.

I reseated the boards, hit the resets, checked the fuses etc., fired it up and voila..it ran a full 20 hours before showing its colors again. Today when I came in the operator says it is errored out in X...and sometimes Z and Y or whatever.

I try re-seating and contact cleaning and scotch brightening and checking everything including pulling and re-seating all the relays, fuses, etc. to see if I have an easy-fix problem. No joy.

When you try to CS, it errors as EMERGENCY STOP TAKE APPROP. ACTION Z AXIS FAULT RESOLVER OR SCALE ERROR

Manual to clear
Jog to reset
Z clears
touch handwheel it errors out instantly with a Z axis Amp Fault
Manual
Jog set to Y
The Y jogs fine
Turn to X
Xaxis fault
reset and try Z
it clears in Z then when you try and move it ...it errors with the resolver/scale error.....

AND...as it sits there...it periodically just drops a rev when it feels like it...
SCARY AS HE_ _

Please, if you can tell me what to look for I'd appreciate it.
Anybody?

[kling8]

I had a similar problem though I didn't crash it the way you did, but when the resolver error flashed up, that was the problem I needed to replace the resolver, I'm thinking that is at least part of your problem, before mine went out all together I was able to run for a while before faulting out. for good. I think we also replaced some ball screws in the Z drive as well, We got a repair man out to fix, and I watched so take it for what its worth. Hope this helps

[kentsui]

Thanks Kling8,
I have replaced ball screws in this machine and tool changer motors and tool holder arbor etc, and I just did a major 1100-2 board replacement on my 3016 myself but this is something I have no experience in. I guess the resolver is in the motor housing for the Z? I did a spindle replacement on one of my Kitamuras and it was in the top motor housing. It sure seems resolver related with that steady drop-drop-drop of the axis when idle. (not too mention the rapid plunge to the table the first time)
Thanks for the input.
I am going to see what else the post generates and see if I can verify that and what else everyone says and then sift it all together and see if I can come up with an answer. A technician is out of the question for me...it is me, or nobody. We have a torn relationship over the last attempt at repair they did and I really can't risk another two weeks down and a bill for nothing.
Thanks again for the info!
Kentsui

[iess525]

I sent you a message...give me a call and I'll try to help you out.

[Delw]

could be a broken coupler also. They do break from time to time and I imagine on the z axis it would cause the same problem as a resolver going bad.
A resolver takes about 20 mins to replace for a novice its extreamly easy. I got some pictures laying around somewere I thought I posted them here a while back ago.
the resolver is right in the back of the motor, take off the cap/cover and its looking you right in the face.
its held to the coupler by a set screw unhook the set screw pull it out.
if the resolver feels gritty or doesnt spin freely chances are pretty good its bad. it should spin free and feel smooth.



iess525:
instead of trying to pimp your business every time someone has a issue with a fadal, you may want to try to answer questions as it helps others as well. The **** is getting old.


Delw

[iess525]

Originally Posted by Delw could be a broken coupler also. They do break from time to time and I imagine on the z axis it would cause the same problem as a resolver going bad. A resolver takes about 20 mins to replace for a novice its extreamly easy. I got some pictures laying around somewere I thought I posted them here a while back ago. the resolver is right in the back of the motor, take off the cap/cover and its looking you right in the face. its held to the coupler by a set screw unhook the set screw pull it out. if the resolver feels gritty or doesnt spin freely chances are pretty good its bad. it should spin free and feel smooth. iess525: instead of trying to pimp your business every time someone has a issue with a fadal, you may want to try to answer questions as it helps others as well. The **** is getting old. Delw

It's easier for me to offer help over the phone instead of typing up a novel online. I invited the OP to give me a call on my personal cell if he wanted help. I don't charge per minute for phone calls if that's what you're thinking.

[kentsui]

Delw,
Thanks for the info.
I will have a look at it Saturday when I can spend all day on it.
Do you think it would allow it to run off if the resolver were bad as well as that deal where it drops a rev on a consistent rhythm?
Nothing gets your attention like Z axis doing its on thing. Makes you scared to ever set a tool again...think I'll get me a role of adding machine tape so I can do it from a couple of feet away
Seriously, thanks for the input. I replaced the resolver on the Kitamura about 10 years ago...got to be similar I'd hope.

K

[masterfabr]

Originally Posted by Delw could be a broken coupler also. They do break from time to time and I imagine on the z axis it would cause the same problem as a resolver going bad. A resolver takes about 20 mins to replace for a novice its extreamly easy. I got some pictures laying around somewere I thought I posted them here a while back ago. the resolver is right in the back of the motor, take off the cap/cover and its looking you right in the face. its held to the coupler by a set screw unhook the set screw pull it out. if the resolver feels gritty or doesnt spin freely chances are pretty good its bad. it should spin free and feel smooth. Delw

I just went through this. IMO it is the resolver. Do you know how to adjust it when replacing so your CS lines up?

[Delw]

resolvers do different things. I am really thinking its a busted resolver couple or bad resolver. but i dont know I am just saying its a very easy check. there are certain things that can be checked by anyone.



I would check the resover first, the coupler. if there ok, check all the wire connections then I would swap the z drive with the x drive, you might even want to swap the x and z coupler.
working with a run away or flacky X is alot less costly then a Z slamming into the table.
then if you cant figure out the problem call a tech.
you did say you got a resolver issue so thats why you should check that first.

are you takeing heavy cuts? lots of peck drilling?

to adjust a resolver is very simple.

boot machine up, align axis's type in cs.
then goto the motor thats off and lossen the three screws, rotate the resolver to the direction it needs to go.
tighten screws/
align marks type cs..

then shut machine off. power up jog the mchine around a little and then to marks. type cs. if they line up you did it. if they didnt repeat steps.

[masterfabr]

Just pull the resolver out,check the coupler,check resolver for ANY sign of bearing roughness while turning armature in resolver with your fingers,check for radial play also. One of my resolvers would turn free as a bird but had maybe .005 axial play and fooled me.Drove me nuts for a couple of days.

[kentsui]

Thank you for your answers. As usual everybody is so helpful and I know that you have been through mess like this a 100 times just like me so I value the opinions and suggestions.

I am diving into the resolver issue this morning so I may need some help. I don't even know what it looks like on a fadal but I bet I'll recognize it when I see it.

If you have any more thoughts please let me know. As I said, a tech is almost totally out of the question. From our end it was a bad-bad situation and resulted in nothing good the last time we used them. I won't go there but the point is that I need this machine badly for ongoing commitments. It has a 36" slide we custom built for it so we could machine 6 foot material for a military job that is very important to us, and to the men/women that need the gear, so I either have to fix it myself or move it out and put a working machine on the floor muy-pronto to meet my commitments.

Thanks again for the suggestions. I'll keep you advised.

[masterfabr]

The resolver looks like a small electric motor about 1" in diameter and maybe 1.5" long.. It MUST turn freely wit no hint of any roughness and no axial play either .I would,if it were me in your situation, get a new or rebuilt one coming today. It is located inside the end cap of the servo. Remove 3 screws and there it is. Loosen coupler setscrew ,loosen 3 screws holding the resolver in place. The screws have an eccentric washer that engages a groove on the resolver so you DO NOT need to remove the screws. 2 small screws hold the circuit board on. 5 minute R&R.To line up the cold start marks you loosen resolver and rotate it till the marks line up. The resolver will need turned maybe quite a ways to get the marks lined up. While the resolver is out check the coupler for damage. If this job is as important as it seems I'd just order a new coupler also and be done with it. I used CNCPros when I bought mine ain the last few weeks (they offer new and rebuilt)but there are other sources. 2 cents