Wobbly Jobo

Discussion in 'Darkroom Equipment' started by Firestarter, Jun 28, 2009.

  1. Firestarter

    Firestarter Member

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    My Jobo CPA 2 drums are looking a little wobbly!

    I know there are lots of stories about the motors wearing etc but the motor spindle on mine does not seem to have any excess play. It also looks like it rotates correctly. To me the coupling magnet seems to be the issue as when I tighten it in place it pulls one way causing it to lean slightly which in turn causes the drums to lean and wobble.

    Has anyone had a problem with the coupling magnet rather than the motor ? Is any one aware of them wearing with use ? I am wondering if the brass collet wears with time and use and causes this problem.

    I can still get hold of a new one but don't want to buy it if it won't cure the problem.
     
  2. Firestarter

    Firestarter Member

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    Has any one here tried curing this problem with a new coupling ?
     
  3. TimVermont

    TimVermont Subscriber

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    Spin the drum by hand, unmounted to check the rollers, and particularly to see that the holes the nylon rollers ride in are still round, and that the roller bases are fully seated. Also check the magnet ring on the bottom of the tank to see that it is fully seated and flat all the way around. Once those are out of they way, then try shimming the coupler you have to see if you can keep it from moving when tightened. You've checked the coupler for cracks and wear?
     
  4. Firestarter

    Firestarter Member

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    Thanks for the reply.

    The roller block is good and there are no cracks or any visible damage to the coupling. The magnet however in the coupling does look very slighlty out of true.

    It all looks good and true until I tighten the coupling retaing screw, then as I tighten it I can clearly see it being pulled to an off square angle. I am almost sure it's the little brass retainer for the brass collet, or the brass collet itself that is worn. I can't really do much to shim this part.

    I reckon my best bet is just to buy a new coupling and hope for the best.
     
  5. Firestarter

    Firestarter Member

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    A new coupling sorted the problem. :smile:
     
  6. domaz

    domaz Member

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    Mine is wobbly too- I should probably get a new coupling but putting two rollers underneath the tank makes it run decently well with an acceptable level of wobble.