Welcome to Our Community

Some features disabled for guests. Register Today.

Slave Motor Moves before Main Axis Motor

Discussion in 'CNC Mills/Routers' started by Cody Alward, Oct 1, 2015.

  1. Cody Alward

    Builder

    Joined:
    Aug 30, 2015
    Messages:
    6
    Likes Received:
    0
    Hello all,
    this is my first post but I've been carousing around awhile.

    I'm running Longs Motor kit on ebay with 4 290 oz nema 23's and the knockoff 6560.

    This is my first OX but it is my second table. I have the same kit. I admit it ran a little rough with that drive and the motors were a little noisier just like this new build. I put a Gecko in it and it is a completely different machine (in a good way).

    My problem is I have a motored slaved to my Y axis on my OX. It always starts moving before my main Y motor. I've switched motors on controller by swapping wires. I've also wired them together in the same port just to test. It always reacts the same. The original slave motor always moves first reguardles of where it is wired. The cable I installed on that motor is actually longer than the main Y axis cable, if that makes any difference.
    Any Ideas? Could it be the motor itself? I was thinking about swapping the Z motor for the slave to see if it moves with the Y.
    Scratching my head on this one.
     
  2. Joe Santarsiero

    Joe Santarsiero OB addict
    Staff Member Moderator Builder

    Joined:
    Oct 30, 2014
    Messages:
    854
    Likes Received:
    181
    Are you using mach3?
     
  3. Joe Santarsiero

    Joe Santarsiero OB addict
    Staff Member Moderator Builder

    Joined:
    Oct 30, 2014
    Messages:
    854
    Likes Received:
    181
    Are you using mach3?
     
  4. Cody Alward

    Builder

    Joined:
    Aug 30, 2015
    Messages:
    6
    Likes Received:
    0
    Yes, sorry. I'm using mach3
     
  5. Joe Santarsiero

    Joe Santarsiero OB addict
    Staff Member Moderator Builder

    Joined:
    Oct 30, 2014
    Messages:
    854
    Likes Received:
    181
    First try sherline mode to see if the problem disappears.
     
  6. Cody Alward

    Builder

    Joined:
    Aug 30, 2015
    Messages:
    6
    Likes Received:
    0
    Found the problem. I feel like a big dummy. I was going to swap motors around and see if I could get the problem solved. As I removed the timing belt I noticed that the timing pulley on the motor in question was a little loose. The motors that came in the kit have no flat spot machined onto the shaft. nothing for the set screw to "lock" into. It was allowing the pulley enough movement to slip but sorta engage. Problem SOLVED. I'm thinking I may just epoxy the pulleys onto shafts. At least that one. The set screws have stripped a little and I don't think I'm getting them truly tight.

    Thanks Joe for your help. I was over-thinking when I should have checked simpler solutions first.
     
  7. Joe Santarsiero

    Joe Santarsiero OB addict
    Staff Member Moderator Builder

    Joined:
    Oct 30, 2014
    Messages:
    854
    Likes Received:
    181
    Glad you found it.
    Have fun.
     
  8. Jonny Norris

    Jonny Norris Veteran
    Builder

    Joined:
    Aug 17, 2014
    Messages:
    495
    Likes Received:
    92
    I strongly advise against epoxying them. In case you want to change belt pitch or pulley.

    The standard pulley grub screws are not up to it. Simply drill and tap new threads for a larger m4 grub screw. I've even used an m4 bolt instead.

    Even without a flat spot it won't twist with one of those in there.
     

Share This Page