Need HELP on LAVA CNC 500

Discussion in 'CNC Machines' started by Bruce Ng., Apr 4, 2018.

  1. Bruce Ng.

    Bruce Ng. New Member

    Hi guys,

    I have a problem with my LAVA machine and hopeless to get support from 3M, bad luck to us that the technician who did service for us retired and we cannot do anything with this. I reckon it is the spindle issue as all the moves are good except the spindle cannot run. Anyone know about this issue?
     

    Attached Files:

  2. DMC

    DMC Scott Hudson

    We can maybe help now.

    Send me teamviewer numbers.

    Do you want to increase your rotary axis from 10 degrees to +/- 20 degrees and add 98mm disk?

    We can do that also.

    I have service manual also. :)
     
    Bruce Ng. likes this.
  3. Bruce Ng.

    Bruce Ng. New Member

    Hi DMC,

    My team and I really appreciate if you can help us with that, we are a bit lucky to know that you are an expert on this kind of machine, 3M is hopeless here in Australia.

    We are more than happy to figure out with you how to improve this machine to the next level, could you tell me the cost and things.

    I need to instal stand-alone teamviewer on my CNC500 to get new password, will update you ID and password soon.

    Thanks in advance :D
     
    DMC and biodentg like this.
  4. DMC

    DMC Scott Hudson

    Your Y-axis has been overloaded (over current limit) and the LUST controller is not happy.
    The Beckhoff software gets error message from One of your Four LUST controllers.
    Milling program stops, or machine does not home (initialize)

    I think you have issue with your Y-axis brake. I think it is stuck engaged.
    This keeps your heavy 4th/5th axis and workpiece from falling down
    during condition of Power-Off. Like when shipping the mill or unplugging the mill.
    Also makes it 10x harder for Y-axis motor to turn the screw and jog the axis.

    This brake is Electro-Magnetic and needs constant power to release the brake.
    Need DC voltage. Measure your DC voltage at the brake.
    Or, feel it. It should feel maybe 50C or so. A little warm for sure.
    It could just be broken and still be warm or receiving power.....but I doubt it.

    You have either bad DC power supply with too little voltage? or wires going to brake? or broken Y-axis brake.
    The Y-axis motor is trying too hard to move the machine.

    .

    Again, Y-axis in your mill is actually Up and Down for moving the workpiece.
    You have a Horizontal mill and not Vertical mill of course.
    Only the Y-axis has a brake.



    DSC_0477.JPG
     
    Last edited: Apr 5, 2018
  5. Bruce Ng.

    Bruce Ng. New Member

    Hi DMC,

    The Y axis brake is fine, I check and it is warm as you said. I also run the Y-axis test from max to min distance and no error comes up. Hence I think that one is okay.

    All the test I run is fine with all axis X Y Z Q1 Q2 Q3 , only stop and error comes up at spindle test. I will send you all the video and photo via PM, hope those info can help you figure out the issue ( I got the bad feeling with the spindle motor or something like that - I think we should replace the UPS or buy a power stabilizer - what you think? )

    Please check you message for the dropbox link and feel free to teamviewer the machine as I leave it on at all time ( our timezone is different so I may not there when you up to work)

    Thanks,
    Bruce.
     
  6. DMC

    DMC Scott Hudson

    How often do you put grease on the collet?

    It really does not need to be done very often.

    Many people use too much and it get inside spindle and screws it up.

    If your spindle is hard to turn....

    Maybe you have bad air valve that blows compressed air into top of spindle to open the collet.

    This pushes the draw-bar down to expand the collet. When no air....spring push draw-bar back up and close collet.

    We have had this 2x. You should not have air going to top of spindle to open the collet during milling.

    Only for changing tool. If Air valve is bad it will leak air to spindle and spindle will resist rotation.



    But, I do not see error message for the spindle man. It is Y-axis error

    It is common for the thermistor (temp sensor) in spindle to be a little too sensitive.

    We add resistor to bring down the voltage a little. To make LUST controller happy with the temp of the spindle. This usually sends over heat error message though. Not an over current error message.


    Does your spindle turn freely??
     
  7. DMC

    DMC Scott Hudson

    No, forget a UPS or voltage stabilizer.
    Not necessary.
     
  8. DMC

    DMC Scott Hudson

    We are scared to move your CNC mill or test anything if you are not there!

    Too dangerous.

    We need you to be next to mill when we play around.

    So, yesterday we only look and not try anything.
     
  9. Bruce Ng.

    Bruce Ng. New Member

    Hi DMC,

    It is me again, sorry not answering you over weekend as I was out of town.

    I have swapped over the Y-axis motor drive to X-axis (in the back) as advised by the service guys in Primacon (via email). But the error stays the same, so nothing wrong with the motor, I am convinced that something wrong with the brake then :(
     
  10. DMC

    DMC Scott Hudson

    Yeah maybe.
    This was my first thought.
    I would first rule out any issues with the brake.
    Don't mess around with anything else quite yet. (too late it seems. lol)

    Measure DC voltage to the brake with machine On and after axis homed.
    That is next step.

    Do you have a variable DC power supply?
    Like used for anodizing Titanium.

    I would apply power to the brake with your mill totally OFF.
    Start with same DC Voltage.
    See if there is a change in resistance to Y-axis movement with brake On and Off.
    Use external power supply to dis-engage the brake.
    Is Y-axis easier to push down by hand when brake is powered? (Disengaged)

    That's how I would test it.

    I might repeat the test with slightly higher Voltage to the brake if you see no change with brake On/Off.
     
    Last edited: Apr 9, 2018
  11. DMC

    DMC Scott Hudson


    What Spindle test are you talking about??
    You mean a Spindle Warm-up?
     
  12. Bruce Ng.

    Bruce Ng. New Member

    No, The NC program for testing embed with the machine. Photo attached.
     

    Attached Files:

  13. Bruce Ng.

    Bruce Ng. New Member

    I just spent whole day to test the Y-axis brake and run the duration test of all axis program, they are absolutely fine, even check with multimeter. Please check the video and photo via link https://www.dropbox.com/sh/16uj1bytlaqe2jf/AACcwElZL4XrJbbUqBk3cK7Za?dl=0


    All the tests stopped at spindle stage, that is the reason why all my thought is that the error caused by spindle somehow.

    Furthermore, at the first time the error came up last week, we were running some job very normally and smoothly, but the spindle, for some reasons, increased the speed, rotated faster in 2 seconds then stop totally. That is why I thought spindle was the part which malfunction although I know the error is related to Y-axis. Confused now, plus my background is not engineer making it even harder :(

    So, If not Y-axis brake, Y-axis motor, what should I test next?
     
  14. DMC

    DMC Scott Hudson

    Start by answering my questions!! :wacky:

    Do I need to type them again, or can you scroll up and read them? :D


    here....

    How often do you put grease on the collet?

    It really does not need to be done very often.

    Many people use too much and it get inside spindle and screws it up.

    If your spindle is hard to turn....

    Maybe you have bad air valve that blows compressed air into top of spindle to open the collet.

    This pushes the draw-bar down to expand the collet. When no air....spring push draw-bar back up and close collet.

    We have had this 2x. You should not have air going to top of spindle to open the collet during milling.

    Only for changing tool. If Air valve is bad it will leak air to spindle and spindle will resist rotation.
     
  15. DMC

    DMC Scott Hudson

    Is spindle hard to turn??

    I do not see you have overheat or overload error for spindle so this is strange for me.
     
  16. Bruce Ng.

    Bruce Ng. New Member

    Sorry for that :)
    Not so often. I do it every 3 months when I check up all the machine. Is 4 times a year too much?

    The procedure I have done for spindle normally:

    1_ Take collet out, steam clean in and out then dry it out.

    2_ Clean the inside of the spindle with air spray and alcohol (isopropanol)

    2_ Put a bit grease on rubber ring on collet and thread then put it back. I never tighten it too hard.

    Not sure when we can check if the spindle hard to turn or not; when the machine is ready? If so, I can feel a bit retention when I turn it, not like very hard but it was just not turning freely.

    It may be the case. As I remember our main air dryer was down for few days and we had to run the machine with the bad air, not 100% dried, which may stuff the machine up.

    How to check it? and fix it?

    P/s:
    The picture I attached it has a red light all the time on location 5 (red circle). Is it normal or it indicates the issue?
     

    Attached Files:

  17. Bruce Ng.

    Bruce Ng. New Member

    At the READY position, are the gauge and light I circled normal?
     

    Attached Files:

  18. DMC

    DMC Scott Hudson

    Spindle should turn easy.
    You should spin it by hand and it goes many full rotations.

    Water does not affect the spindle. Ceramic bearing!
    I have pumped gallons of water through my spindles and no damage.

    We stopped using grease on collet maybe 5 years ago?
    When I did use it....it was only 1-2x a year and we use VERY small amount.

    So.....you choose "Spindle Run-in" option and hit start and spindle does what??
    Spin a little bit?

    Forget those lights on Air valves.
    The problem is that the air valves will all fail!
    They allow air to pass, even when Red or Green light is OFF.

    This could push down on spindle draw bar and make spindle hard to turn.
    I take pic and show you what air line to check.....hang on
     
  19. DMC

    DMC Scott Hudson

    See this Blue air-line?
    It should NEVER have air pressure EXCEPT when collet opens to change tools.

    Please pull off this Blue air line and check for air flow.
    Machine need to be ON and not in Stand-by mode.

    Machine should wake up and you home all axis....then check air line.

    In One pic....I am pointing at a metal part that comes down and pushed the draw-bar to open collet.
    This will rub on rotating assembly and prevent spindle from turning easy and make bad sound.

    Scotty DSC_0478.JPG DSC_0480.JPG DSC_0479.JPG
     
  20. DMC

    DMC Scott Hudson

    If you have air pressure then you need to replace the SMC Air valve.
    We have done this many times!

    3A opens collet.

    Eventually all these SMC air valves will leak air and need to be replaced.
    Could be 5 years? Could go bad in 15 years?
    To test, just see if air is going to spindle.
    Press the Red round button and collet opens with air pressure.
    No RED LED and also NOT pressing Red button collet closes, AND you need to verify that no air pressure is going to spindle.



    .
    see this.jpg
     

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