584,833 active members*
5,486 visitors online*
Register for free
Login
IndustryArena Forum > MetalWorking Machines > HURCO > Scary VM10U problems
Page 2 of 4 1234
Results 21 to 40 of 69
  1. #21
    Join Date
    Jun 2008
    Posts
    1103

    Re: Scary VM10U problems

    I had to sort out a coolant through spindle leak on a machine in Frankfurt that had the same model of Fagor encoder inside the head assembly. The encoder was half submerged in coolant that had been there for weeks and it still worked fine. I’m going to pull the drawings for the BRC200 table tomorrow and see where this brass ring is supposed to be as I’ve never encountered one during table rebuilds. Normally, anything that needs sealing is done with o-rings or cup seals on the rotary axes.

  2. #22
    Join Date
    Jun 2006
    Posts
    424

    Re: Scary VM10U problems

    It might be because the rubber seal functions if the shaft on the encoder is indicated into center. Maybe it was an engineering problem compounded by a machine assembly quality issue. The rubber seal on the encoder shaft would not seal beyond a certain amount of coaxial alignment error of the shaft to the mounting position. The C axis encoder is a style designed to tolerate some error of alignment in assembly, but I noticed that regarding the seal.

    Regarding your floating encoder- man I wish I had your luck. It would have saved me some money. If they were submersible, I would be $4600 heavier in the wallet right now, and that's a lot of hookers and blow.

  3. #23
    Join Date
    Jun 2006
    Posts
    424

    Re: Scary VM10U problems

    We received some PDF's from Hurco support, ordered O-rings from McMaster Carr, and spent a day replacing the o-rings in the A and C axis - the A is on both sides of the trunion so that is like a day and a half job. Now we're going to run the machine and hope to see if we are out of the woods on the table slipping. The brake itself was mint- not wear evident at all.

  4. #24
    Join Date
    Jun 2006
    Posts
    424

    Re: Scary VM10U problems

    We also changed the C axis error limit from .002 to .005 degree to match the A axis in parameters. We haven't had an alarm in 2 shifts. So maybe the O-rings helped. As a side note, we're dealing with 85PSI or so of air on the Hurco C axis, our little Doosan Lynx 220LYSC has 600PSI hydraulic on its disc brake for the C axis. So 7 times the braking force. It actually has a low clamp we have set at about 85PSI (factory recommends 85-135PSI) that is for dragging the brake when C axis cutting like thread milling when you aren't doing positioning and using X/Y/Z G01 Feed moves. The larger machines have a direct drive 30HP motor so they don't need low clamp braking.

  5. #25
    Join Date
    Jun 2006
    Posts
    424

    Re: Scary VM10U problems

    Problem came back, the machine is down more than it's up. Now most recently the cutting is pushing the C axis around and it's losing the encoder position. That doesn't make any sense to me. The encoder shouldn't ever lose position- from what I understand it is a glass scale and it should always know where the table is even if the table moves in an undesirable manner (the servo and the encoder have different responsibilities- the servo to move the table, and the encoder to know at all times where the table is).

    The C is being pushed enough to trip the parameter and stop cutting, and re-zeroing isn't returning the table to the same position. I wish this was a problem someone could guaranteed fix for some amount of money but I feel like if I had Hurco service it, they might be servicing a good working machine of this type and that they might leave and the machine continue to operate like this. We have had it serviced recently by hurco- the new encoder install. We have rebuilt the o-rings, so it's absolutely air tight- when we were in there the brake metal parts seemed minty fresh. I don't get it. We have a Mazak with a Nikken 4th- it operates perfectly fine. We have a Mazak VCU 500A 5X and it works. We have 5 subspindle lathes with Fanuc controls and they operate 10 combined rotaries that never lose position and always work right. This Hurco rotary doesn't work right and I can't wrap my head around it.

  6. #26
    Join Date
    Dec 2013
    Posts
    5717

    Re: Scary VM10U problems

    Quote Originally Posted by Green0 View Post
    Problem came back, the machine is down more than it's up. Now most recently the cutting is pushing the C axis around and it's losing the encoder position. That doesn't make any sense to me. The encoder shouldn't ever lose position- from what I understand it is a glass scale and it should always know where the table is even if the table moves in an undesirable manner (the servo and the encoder have different responsibilities- the servo to move the table, and the encoder to know at all times where the table is).

    The C is being pushed enough to trip the parameter and stop cutting, and re-zeroing isn't returning the table to the same position.
    I would say that there is a mechanical disconnect between the encoder and the table, or the encoder and/or wiring is defective and there is noise on the line. I guess the problem could also be the encoder counter on the controller.

    I would expect the axis to trip out (thus shutting down the machine) on an excess position error, but it should not lose the table position unless the encoder signal is not properly getting to the controller or is mechanically slipping.
    Jim Dawson
    Sandy, Oregon, USA

  7. #27
    Join Date
    Jun 2006
    Posts
    424

    Re: Scary VM10U problems

    Quote Originally Posted by Jim Dawson View Post
    I would say that there is a mechanical disconnect between the encoder and the table, or the encoder and/or wiring is defective and there is noise on the line. I guess the problem could also be the encoder counter on the controller.

    I would expect the axis to trip out (thus shutting down the machine) on an excess position error, but it should not lose the table position unless the encoder signal is not properly getting to the controller or is mechanically slipping.
    We tightened the jam nut on the encoder to the table and check tightened the bracket, so the belief is that the encoder is not mechanically slipping. The end mill is pushing the C position during a cut, or feedback is happening during the cut because we can see movement of the C axis registering during the cut before the machine stops cutting. At that point the table is now moved is the new part of that problem.

    I agree with your thoughts. What I guess is terrible about having this problem is that I don't get the feeling Hurco has the knowledge to send a tech who is able to 100% definitively diagnose and fix this machine inside that visit or even two visits. I wish I had a better feeling about their technical ability to resolve it so it doesn't re-occur. On our Doosan machines, I have about 100% confidence that ellison will resolve a problem. The biggest difficulty in saying 100% is that we just don't have problems with the Doosan machines- they are nearly unstoppable brick ****houses. On our Mazaks it seems mazak can troubleshoot and identify the problem but may have trouble getting a field tech out to work on it. On our Yama Seiki's, Yama seems very good at diagnosing and can get people on a plane if the customer wants them on the plane to fix it. On the hurco, we can get a tech out, but we've had different support here twice (once an encoder had failed, this last time it was believed the marker was too close to the proximity switch in degrees, we also replaced all the brake O-ring seals, and the problem is still here, and has even developed now into a second problem of losing position of C.

    This could be the wiring, the servo, servo wiring, or servo drive, the plc, the encoder, or the brake, or a combination of these. If it was an encoder, it would mean the Fagor IP64 (not waterproof, but humidity resistant) encoders might only last 2 months in the field.

  8. #28
    Join Date
    Dec 2013
    Posts
    5717

    Re: Scary VM10U problems

    I guess another possibility is that there is slippage between the drive and the table. In the drive system, if there is some kind of mechanical connection between where the encoder is connected and the table then the problem could be there.
    Jim Dawson
    Sandy, Oregon, USA

  9. #29
    Join Date
    Oct 2004
    Posts
    188

    Re: Scary VM10U problems

    Has anyone checked the belt between the servo motor and the rotary table. pull that cover off the front of the C axis, the belt should be tight and take some finger pressure to move..if the the brake was bad and It leaked oil or coolant got into the cavity it could have made the belt weak,
    the brake should for the most part hold it in position but there are special circumstances that can over come the brake. I have seen people have A axis at 90 the a long part drilling with a large bit outside the radius of the table.it over torque the c axis. just strange now one can zero in on it.

  10. #30
    Join Date
    Aug 2019
    Posts
    339

    Re: Scary VM10U problems

    You should have received a support contract upon reception of your machine tool. Therefore, and *in the real world*, we normally log mechanical failure and when this was reported to the supplier's support in-writing (down to the minute). This should be CC'ed to both supplier's sales mgt & support teams with scanned signatures. Needless to add that this log should include any financial losses due to the equipment failure(s). Taking the proper steps in getting your suppliers to fulfill they promise, and to prevent them from suffering from a breach of contract, can lead to some quite impressive response time customer service-wise (talking about hours, max!).

    Equally important; and if "out of service contract", your internal risk mgt team should have a budget for spares and/or emergency replacement parts from at least two different suppliers (with PO ready for this).

    Irrelevant to your current mechanical issue, I understand, although I hope this could help in the future.

    G'luck

  11. #31
    Join Date
    Jun 2006
    Posts
    424

    Re: Scary VM10U problems

    Quote Originally Posted by Jim Dawson View Post
    I guess another possibility is that there is slippage between the drive and the table. In the drive system, if there is some kind of mechanical connection between where the encoder is connected and the table then the problem could be there.
    This is the major problem- the Hurco support phone puts a wait of several hours between the customer and getting some form of communication back. So the process is segmented into many 3-8 hour blocks of communication hoping to reach someone with some mechanical understanding of the machine such that they can take the symptoms and diagnose the source of a problem to resolve.

    I have no confidence we've reached anyone who has total understanding to the effect they can actually take the symptoms and diagnose a source to target for repair, so it seems more like we would have technicians out who would confirm the table moves under its own power with no cut, leave, and we would have continued issues and need for more 3-8 hour blocks of lost time communicating on a path to a solution. Not having any understanding of the length of time between us and a solution or the cost, it is really tough to make a financial assessment of what makes sense. It leaves you wishing the machine was 3 axis with a 4th rotary or something more simple that could be diagnosed and repaired effectively in the field.

    This machine is in a 4 machine cell, and the settup operator in the cell loses production on one or more of the other machines when he spends time trying to work the Hurco support for some sort of information or path to a resolution. It's unlike any other manufacturer support problem we've ever had, it seems more like hopeless. What you want to hear is, "for $6000 we can have that reliable for the next several years or something like that." not watching multiple attempts fail to resolve the problem for more than a few weeks.

    I just called a local supporting dealer here and after explaining what has happened asking if they had confidence and knowledge to work on table issues and they suggested they didn't know much about the rotary table issues and we should continue to work with Hurco for support. It is odd because the VM10U is the entry level 5 axis machine, so it would seem that it should be the most common 5 axis machine in the Hurco lineup, and the most known and understood.

  12. #32
    Join Date
    Dec 2013
    Posts
    5717

    Re: Scary VM10U problems

    I think this machine is going to be a never ending battle until you drag it out the door. Here is the solution https://us.dmgmori.com/products/mach...ing/dmu/dmu-50
    Jim Dawson
    Sandy, Oregon, USA

  13. #33
    Join Date
    Jun 2006
    Posts
    424

    Re: Scary VM10U problems

    Quote Originally Posted by Jim Dawson View Post
    I think this machine is going to be a never ending battle until you drag it out the door. Here is the solution https://us.dmgmori.com/products/mach...ing/dmu/dmu-50
    If Hurco support never improves I think you're totally correct. I don't even look at 3 axis Hurco's anymore, it's just too much risk to have even a decent machine that has low quality support.

    We have a Mazak VCU500A-5X here and the only issue with it is that the settup parameters aren't perfect for TCPC so we are probing parts on different rolls to make good cuts with it. It arrived with a warped trunion leg because it was shipped with a pad loaded on the truck, and there are a few thousandths the table is not flat on account of that far leg being pushed upward from centerline. The Hurco TCPC worked good until the table started to lose its encoder position. The DMU-50's are interesting I've seen a few almost new at affordable prices like $99K but usually with 8000RPM spindles and we're cutting aluminum so it seems like that would be pretty slow.

    The hurco can make impressively accurate work when the machine is letting itself cut through a program, but the table brakes are very weak so you have to really baby the heck out of it or it's going to trip over itself- refuse to go on, or worse lose table position completely.

  14. #34
    Join Date
    Dec 2013
    Posts
    5717

    Re: Scary VM10U problems

    If that Herco were in my shop, I would just make it work like I wanted. If that means re-engineering the system and replacing all of the controls then that would happen. I can't imagine bringing in tech support to service my equipment. I am the tech support, even for my new Haas.

    But, my shop is not a commercial high production environment, just a step above a home hobby shop. My production is limited and is for my own in-house products with a little product development and prototyping thrown in. Sometimes my machines sit idle for weeks at a time. If I were trying to make a living as a real production job shop then I would replace the machine with something that would make me money rather than cost money.
    Jim Dawson
    Sandy, Oregon, USA

  15. #35
    Join Date
    Aug 2019
    Posts
    339

    Re: Scary VM10U problems

    You must have a technician in your shop who can trace (log) the encoder's signal? There are only 3 signal wires on a scale (??), get him/her to do some work a bit. Establishing whether the encoder, joints or plc is at fault takes roughly an hour or two. Ideally you'd also need to trace the time the brake takes to engage and disengage (in ms) and sync the motion. I'm suspecting rotation before the brake's full disengagement - that could be a reason your encoder gets fooled. You've tried placing a short period G4 before rotations and see if that helps?

    What sort of control/plc Hurco runs on this VM10? looks like a custom siemens vnck package

  16. #36
    Join Date
    Jun 2006
    Posts
    424

    Re: Scary VM10U problems

    Quote Originally Posted by Mecanix View Post
    You must have a technician in your shop who can trace (log) the encoder's signal? There are only 3 signal wires on a scale (??), get him/her to do some work a bit. Establishing whether the encoder, joints or plc is at fault takes roughly an hour or two. Ideally you'd also need to trace the time the brake takes to engage and disengage (in ms) and sync the motion. I'm suspecting rotation before the brake's full disengagement - that could be a reason your encoder gets fooled. You've tried placing a short period G4 before rotations and see if that helps?

    What sort of control/plc Hurco runs on this VM10? looks like a custom siemens vnck package
    The control is Windows NT or something like that based. We don't have people here who can troubleshoot the trunion or electronics internal to the company and hurco techs have been out here. It almost seems like ideal for the machine would be a rebuild service where they just took it apart, inspected, and reassembled with torque wrenches and stuff to confirm everything was put together to whatever specifications they have, and replacement components used if needed. That might fix it. In Taiwanese machines, there are often assembly issues that cause problems to happen in my limited experience with Taiwanese machines. I prefer to buy Japanese or South Korean machines on account of their higher quality in my experience. I've had not the greatest luck with Taiwanese machines.

    I think Taiwan could do the world a service and just get out of CNC machines altogether.

  17. #37
    Join Date
    Jun 2006
    Posts
    424

    Re: Scary VM10U problems

    Quote Originally Posted by Jim Dawson View Post
    If that Herco were in my shop, I would just make it work like I wanted. If that means re-engineering the system and replacing all of the controls then that would happen. I can't imagine bringing in tech support to service my equipment. I am the tech support, even for my new Haas.

    But, my shop is not a commercial high production environment, just a step above a home hobby shop. My production is limited and is for my own in-house products with a little product development and prototyping thrown in. Sometimes my machines sit idle for weeks at a time. If I were trying to make a living as a real production job shop then I would replace the machine with something that would make me money rather than cost money.

    I envy the concept of having time, and your skill with fixing your machines. We had a Mazak go down for a spindle motor and a guy here was able to replace that successfully, but Mazak helped us with a little information on the phone on account of not having a service tech available in the area for 2 weeks. That same guy re-aligned the ATC arm and got it working good. Another guy here can install the encoder now on the VM10U having been trained by a hurco tech and has done that successfully- he also swapped the O-ring seals on the brake clamp mechanisms for A and C successfully. The Lathe department manager realligned a Yama Seiki with me in a couple days and a Doosan in a few hours, but we're at a loss sometimes without good supporting information- I don't have any info to use for disassembling the C axis so I would be a little afraid of what might negatively happen worst case.

  18. #38
    Join Date
    Dec 2013
    Posts
    5717

    Re: Scary VM10U problems

    Quote Originally Posted by Green0 View Post
    I envy the concept of having time, and your skill with fixing your machines. We had a Mazak go down for a spindle motor and a guy here was able to replace that successfully, but Mazak helped us with a little information on the phone on account of not having a service tech available in the area for 2 weeks. That same guy re-aligned the ATC arm and got it working good. Another guy here can install the encoder now on the VM10U having been trained by a hurco tech and has done that successfully- he also swapped the O-ring seals on the brake clamp mechanisms for A and C successfully. The Lathe department manager realligned a Yama Seiki with me in a couple days and a Doosan in a few hours, but we're at a loss sometimes without good supporting information- I don't have any info to use for disassembling the C axis so I would be a little afraid of what might negatively happen worst case.

    It sounds like your operation is large enough to support an in-house mechanic/electrician. Finding the right guy with the right skill set might be a bit difficult but there are a few of us out there. A well rounded millwright is what you really need. A good millwright should be able to do anything in an industrial environment. Doesn't have to be a machinist, but should be able to competently operate any machine tools as well as repair them.

    Maybe the next time one of the service techs comes to your shop, make him an offer. I was a traveling technician for about 20 years, and I can tell you I was pretty burnt out after a few years of living on airplanes. If someone would have offered me a job at anywhere close to what I was making I would have seriously considered it.
    Jim Dawson
    Sandy, Oregon, USA

  19. #39
    Join Date
    Jun 2006
    Posts
    424

    Re: Scary VM10U problems

    Quote Originally Posted by Jim Dawson View Post
    It sounds like your operation is large enough to support an in-house mechanic/electrician. Finding the right guy with the right skill set might be a bit difficult but there are a few of us out there. A well rounded millwright is what you really need. A good millwright should be able to do anything in an industrial environment. Doesn't have to be a machinist, but should be able to competently operate any machine tools as well as repair them.

    Maybe the next time one of the service techs comes to your shop, make him an offer. I was a traveling technician for about 20 years, and I can tell you I was pretty burnt out after a few years of living on airplanes. If someone would have offered me a job at anywhere close to what I was making I would have seriously considered it.
    I agree with you. The better service techs would be great team members at a shop, I don't really know what they make. My impression was very high. I know the companies bill at $150 an hour. I've thought about it. I wonder what their hourly pay plus benefits is? I could see floating $35 an hour + 70% family coinsurance pretty easily to take 95% of service calls and put them in house. We probably only run $30,000 per year of actually billed $150/hour service time here, but to have someone who could write fanuc ladder, maybe program mastercam, or integrate accessory equipment on the floor could easily make the cost basis for the extra money. After a guy could show a benefit he could earn a raise from there. Take that crazy service tech schedule and stress level and compartmentalize it to one shop, and I think that guy is really getting a break personally.

    The bigger issue though is that IMO the only service techs worth having on staff would be the senior applications people. The most knowledgable guys.

    This isn't a cost problem- if Hurco can fix the C-Axis for $6000 I would pay it. I just need to understand they actually want to be comprehensive and solve it in a way that the machine will be reliable for 4-5 years on the solution provided. I don't need a 80% travel bill on a bandaid to this problem that gets me back to screwed in 2 months. Machines on the floor need to be dependable for the capacity they represent or you end up buying redundant equipment to consider 2 machines as providing the capacity of 1 and that game isn't my favorite strategy.

    With Ellison, our Doosans have been good at representing their actual capacity. The Doosan machines thus far have been reliable such that 1 machine represents 1 machine.

  20. #40
    Join Date
    Dec 2013
    Posts
    5717

    Re: Scary VM10U problems

    When I was employed by a company as a senior field tech my ending pay, in 2000, was salaried at $80K annual (about $40/hr) + benefits, I don't really remember what the whole package was. In reality, my hourly rate was a lot less that that because of the on-the-job hours, including travel time, were well over a 40 hr week on average. I was traveling all over the US, Canada, Mexico, and South America. I suspect the techs that you are working with do not have that wide of a service area. I am guessing $35/hr would get their attention.

    Based on what you have described I'm going to make a guess that Hurco can't fix your A/C axis. It's just a poor design and they are not going to re-engineer and rebuild it. In my shop I would just build one that would work, or completely redesign the Hurco and make whatever mods are needed. In your case maybe do an EBay search for ''trunnion table'' There are a couple of nice Haas units and a Tsudakoma listed, not sure if they would work with your cutting envelope. Adapt the controls as needed.
    Jim Dawson
    Sandy, Oregon, USA

Page 2 of 4 1234

Similar Threads

  1. Replies: 3
    Last Post: 09-14-2018, 12:44 AM
  2. VM10u and Renishaw probe
    By Papa_lazerous in forum HURCO
    Replies: 2
    Last Post: 04-01-2014, 02:32 AM
  3. vm10u 5 axis program examples
    By timf in forum HURCO
    Replies: 1
    Last Post: 03-16-2011, 08:56 PM
  4. Replies: 4
    Last Post: 11-08-2010, 01:38 PM
  5. hurco VM10U 5 axis processor
    By timf in forum EdgeCam
    Replies: 1
    Last Post: 04-01-2010, 09:31 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •