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  1. #381
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    Hi!
    That is right... I have noticed... I tried to get it back through the fill port but that was not so easy... A brass ring seems to be used to press the filter in place in the top lid of the housing... Might give it one more go but otherwise I think I leave it as it is and make sure to use a funnel with a filter... I am not so keen on dissasembleing the tank...

    /Kammlake

  2. Likes Nerv, HBOB liked this post
  3. #382
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    Dissembling the Lub oil tank would be a walk in a park compared to all the Z axis problems . Look's as if the Tac is the problem.
    I was really hoping the 3TRN2 and servo motors were OK. Facts are facts ,and useing a Ohm meter at the Tac commutator (bus bars)
    eliminates all of the - what if - check that - look at something else. Think you deserve a "Good Job / Well Done" medal.

    I am interested in what your fix/repair will be. Looked at my MH600E and noted the MDC 10 . 20 F????? servo motors had the same
    Tac voltage value on their labels. Also the 3TRM2 modules for each motor had the same 9V at 2000RPM value for the 3 different Tac inputs.

    My thinking is a used replacement Tac from any Indramat MDC ??.?? servo motor might work, My MDC 10.20F labels show 0.317Vs/Rad.
    for Tac output. Would be interesting to know if the shaft diameter ( at Tac mounting position) varies/changes with motor size.

    Have read when re-installing the Tac to use a new crush washer an use new carbon brushes if replacing the Tac with a different or new one.
    If you get a chance ,could you measure the motor shaft diameter at the position where the Tac mounts?

    Wonder what caused the Tac failure? Think I would be Ohm meter checking the orange wire cable going to the motor to see if any of the power wires
    (motor or brake wires ) might be shorting to the Tac wires.

    Hope you can find some cheap replacement parts. If not cheap then at least reasonable cost. Please keep us posted on your thoughts and
    what you are finding.

  4. #383
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    Hi!
    I have three alternatives. First one is to replace the whole motor. I think I might be able to trade one for something I have laying around. However I suspect that it is not really the same motor (looks longer). Second option (if I get hold of that motor) will be to pull out the tac of the "new" motor (assuming it is the same) and use that as a replacement part.

    Regarding the washer you are right. It is stated in the manual. I have however not found anything about new brushes... I hesitated to pull out the tac because of that washer but I had to move forward so I just did it.... Now it is in place again with that same non-reusable washer.... Will have to think about that one when doing the permanent fix...


    Option three is to replace the tachometer with an electronic one. Since I could not find any suitable I would build it myself. I would use a magnet on the shaft and a modern rotary hall sensor chip outputting the angle. Then I would write some software for a microcontroller that outputs a voltage that is depending on the angular speed....

    First I will see if I can get hold of that motor....

    I will try to remember to measure the shaft next time I dissasemble the motor.

    /Kammlake

  5. #384
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    Hi Guys,
    I have a Maho 600E but cannot find the constants pages. I would love to know if anyone out there has the machine constants for this machine. The control is Phillips 432.

    Thanks in advance,
    Brett

  6. #385
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    Hello!
    I have now solved my z-axis problem. I thought I share some pictures and how I did it... Unfortunately I now have another problem.... :-( see next message...


    So my tachometer was not working and I didn't understand how to fix it so I was looking for spare parts. In the meantime I tried to design my own tachometer. I used a rotary hall sensor and a microcontroller hooked up to some driver circuit generating the output signal proportional in amplitude to the speed of rotation.

    I actually managed to get it sort of working.... It looked quite good on the scope. However when I tried it on the mill I got oscillations again... but this time different ones depending on a too slow response of the tachometer. Also I had some problem with my voltage output stage.... I suppose I can get this thing to work if I put some more effort in

    IMG_21831_14537.jpg - Google Drive
    IMG_21831_1223.jpg - Google Drive
    IMG_218311_386.jpg - Google Drive

    After some dissapointment of not getting it to work I managed to get hold of some spare parts. I got three motors and a trm2 servo driver unit. I traded them for a lath chuck, some ball screws and some other tools I had laying around.

    The motor I got was slightly bigger than the one I have on my Maho. Since the servo driver is the same I figured it would work but I finally pulled out the tach on the new motor and pressed it in place on the old motor (by reusing the non-reusable shim...).

    After putting the thing together it worked immediately!!! :-)

    The sound from the z-axis now sounds healty again and not a trace of the oscillations.


    So I started to use the mill for some projects with success.... for some time.... (to be continued)...

    /Kammlake

  7. #386
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    So....

    After some hours of happy milling my machine was totally dead again. Showing error code Y09 (dont have the exact name of the code now but something like "dynamic distance error").

    I read something about that the lamp can break.... I dissasembled the glass scale and could not see any light comming out. I took out the "bulb holder" and measured the resistance to confirm that the lamp was broken. I have no idea what kind of lamp that is (could not find anything on the internet either...). I put in a white LED instead. I really have no idea how much light there should be etc. but I gave it a try.

    The result right now is that nothing is working. I asume one have to trim the position of the lamp. Maybe also the intensity. I have no idea how to do that. Anyone with experience from this???

    Only difference is that when I had the scale reading head dissasemblied and turned on the mill I could tap pretty much anywhere on the head to get the error Y09. After installing the LED I cannot do that. I have to try to move the axis to get the error code.


    So right now I get no signal at all. At least I get no DRO increments when moving along the scale. Any suggestions on how to proceed. How bright should the lamp be? Is there a method for positioning the lamp? I took some pictures...

    Any help is most appreciated!!!

    IMG_218324_113132.jpg - Google Drive
    IMG_218324_113141.jpg - Google Drive
    IMG_218324_122659.jpg - Google Drive
    IMG_218326_22355.jpg - Google Drive
    IMG_218326_22443.jpg - Google Drive
    https://drive.google.com/open?id=1Ti...uNCPwJfAP97eXu
    https://drive.google.com/open?id=1zf...4-ZIJolQ9L0yLS
    https://drive.google.com/open?id=1ee...GwpnWx_PkcQo00
    https://drive.google.com/open?id=1gM...nz6gGHaQANZrl6
    https://drive.google.com/open?id=137...5AqrNrCq3tiNkk


    /Kammlake

  8. #387
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    Kammlake You asked for any help,but I hope others will come with some real answers for you. The light bulb is (to me ) referred to as a "Grain
    of Wheat" style miniature bulb. That type or style of bulb is/was used in model trains-doll houses - medical gear- etc. Those bulbs came in
    various voltages and expended hours of use and also lumens or brightness/colour. I suspect the photo cell sensors are more sensitive to infrared
    than white light. That may be why the LED is not working ? Do know that infrared LEDs are a common available type. My guess is a LED emitting
    the lower frequency range of infrared might work. Again the key is what frequency/colour the photo cell sensors are sensitive to.
    If I was trying to find a usable light "Colour" ,think I might try to Scope the scales Exe. Board and shine the light source threw a moving Hair
    comb onto the photo cell sensors to see what the results are. The hair comb is used to simulate the markings on the scales glass spar.
    Glad to read you got the Y axis motor working. To bad it was so costly in usable stuff. Hope you do more with the Hall effect replacement for
    the motor tach. Also,a big Thank you for the very good Photo's. They are a big help for present and future MAHO owners.

  9. #388
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    Thanks for those photos. Do you have a photo of the bulb you removed, out of the housing?

    On my MH400E, I had issues with the Z (normal Y) axis distance not matching the commanded move. Cleaned the scale, and sense head with IPA and digital camera sensor swabs, and now it works perfectly again. The instructions are here:
    Retrofitting a 1986 Maho MH4E - Page 32 - LinuxCNC


    My vertical axis gives no signal though, so I suspect a dead bulb like yours had. I haven't started trouble shooting it yet. Do your scales have 12V bulb power? Do the bulbs in ebay ID 230958896783 look similar?
    Mark

  10. #389
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    Im located in Sweden, but I have all three servos, drive, color screen etc. for sale from my MH 500C. If you are interested, mail me and well continue there.
    [email protected]


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