Z axis trouble

Discussion in 'Calibration, Help, and Troubleshooting' started by Jason, Apr 6, 2017.

  1. Jason

    Jason Member

    Joined:
    Jul 13, 2016
    Messages:
    4
    Likes Received:
    1
    Started having trouble with the Z axis on our printer. It has worked fine for over a year then after adding octoprint to it (which I don't think affected it) I'm having problem with the left stepper motor acting oddly. When the printer homes the left motor seems to hesitate when it starts to move and then again when it changes directions thus making the bed no longer level. I've tried several things already, changed the stepper driver, increased the voltage, changed the stepper motor and checked the bed tramming. In the video you can see the left motor hesitating when I change directions just moving the bed up and down. Anyone have any thoughts?

     
  2. Rob Heinzonly

    Rob Heinzonly Well-Known Member

    Joined:
    Sep 20, 2015
    Messages:
    362
    Likes Received:
    125
    Did you check the cable ? One test you could do is swap the cables of each stepper motor and see if this will affect the other motor or not.
     
  3. Stian Indal Haugseth

    Stian Indal Haugseth Well-Known Member

    Joined:
    Sep 11, 2015
    Messages:
    573
    Likes Received:
    95
    I agree with @Rob Heinzonlys assesement. Probably a bad connection somewhere.

    Probably a connector or in worst case in the wire it self.
     
  4. Old_Tafr

    Old_Tafr Well-Known Member

    Joined:
    Mar 7, 2016
    Messages:
    560
    Likes Received:
    75
    Lubrication? Plenty of grease is good but wipe of the surplus after running the bed up and down so that it does not attract too much dust and dirt. Lubricate both smooth rods and lead screws.

    Loose screw? At any of the three points the lead screw passes through, or even the screws holding the Z motor have come loose?

    Equally if the smooth rods supports are loose they could be out of alignment.

    The lead screw or smooth rods being out of alignment would cause more friction and cause the motor to stall momentarily (English form of momentarily)

    A rather extreme test would be to remove the two lead screws and move the bed up and down by hand checking for resistance.

    The two Z motors are also wired in parallel? so other than a poor connection to one motor it's not likely to be the driver board as both driven from the same one. Swapping the cables is possible but difficult as you would have to do this at the motor end.

    Y axis smooth rods loose? This would cause the frame (unsupported at the front) to move outwards or inwards creating more friction.
     
    #4 Old_Tafr, Apr 7, 2017
    Last edited: Apr 7, 2017
  5. Kanedias

    Kanedias Well-Known Member

    Joined:
    Sep 12, 2015
    Messages:
    406
    Likes Received:
    124
    You didn't tin the bare ends of the wires connecting to the rumba by any chance?
     
  6. Old_Tafr

    Old_Tafr Well-Known Member

    Joined:
    Mar 7, 2016
    Messages:
    560
    Likes Received:
    75
    The theory being that the screw connection on a tinned wire starts to come loose after a while?
     
  7. Jason

    Jason Member

    Joined:
    Jul 13, 2016
    Messages:
    4
    Likes Received:
    1
    I finally found the problem, it was the wiring. One of the wires going into the connector on the rumba was broken right at the terminal apparently. No visible damage so it must have gotten pinched or bent over and broken somehow while I was working on it. Good news is I've had the whole thing apart and everything has been cleaned and re-lubricated. Had a successful print so I think it is back online. Thanks for all the help!
     
    Stian Indal Haugseth likes this.

Share This Page