545,767 active members*
1,834 visitors online*
Register for free
Login
IndustryArena Forum > Laser Engraving and Cutting Machines > Commercial Laser > G.Weike Laser > G Weike LG900N laser head cannot move left
Results 1 to 4 of 4
  1. #1

    Join Date
    Aug 2018
    Posts
    44

    Angry G Weike LG900N laser head cannot move left

    Hello, I purchased a G Weike LG900N 80W CO2 laser cutter ~1.5 years ago, and it has worked great at mostly light usage, until now.

    But recently it developed this horrifying problem: the laser head sometimes loses the ability to go left. When I press the "move left" button, it goes right instead. Same thing when it tries to cut. When I first power it on and it tries to home itself, it just winds up banging onto the rightmost rail with a scary "BANG BANG BANG" sound, until I reset it.

    I thought perhaps the X axis stepper motor was bad, and replaced it, but that did not fix it. Same problem.

    I thought the problem was maybe caused by heat, because it would get into this state after quite a while (maybe an hour) of usage, and sometimes turning it off, letting it cool, and then on again, might fix it. But it's been off for days now, and I turned it back on and the same problem is there.

    Has anyone else seen this problem? Could it maybe be a loose wire? How do these stepper motors know which direction to step in, when commanded? (Like which wires get which volts?) Or maybe a short circuit in the control panel (the board that has the buttons that I press)?

    Any suggestions on how to debug or fix it? I could try replacing the whole control board, which seems to be on the lower back of the machine. I'll try to get its exact part number.

    Thanks!

    Mike

  2. #2

    Join Date
    Aug 2018
    Posts
    44

    Re: G Weike LG900N laser head cannot move left

    I took pictures of the controller (RDC6442S-B(EC)) and the X/Y/Z drivers (not sure what part number they are, but they have big black heat sinks on them), and attached here.

    I think I will just try to replace that controller first, and if that fails, the drivers.

    I found a newer Ruida controller, the RDC6445G, on Amazon. Do you think I could just upgrade to that newer controller as long as I can physically mount it in the machine, along with its control panel? Or should I try to find precisely the right model?

  3. #3
    Registered
    Join Date
    Nov 2008
    Posts
    496

    Re: G Weike LG900N laser head cannot move left

    Pin 1 off your controller is X direction
    Looks like it has an LED showing state to help know what signal comes from the controller. Left on or off and right the opposite.
    I would remove and reinstall that connector at both ends.
    So the signal out of the controller is 5 volts. It connects to a stepper driver that drives the stepper motor. Loose wires at to stepper wouldn’t show up as a direction change.
    Most likely the problem is in the pin1 wire.


    Sent from my iPhone using Tapatalk

  4. #4

    Join Date
    Aug 2018
    Posts
    44

    Re: G Weike LG900N laser head cannot move left

    Quote Originally Posted by Dean448 View Post
    Pin 1 off your controller is X direction
    Looks like it has an LED showing state to help know what signal comes from the controller. Left on or off and right the opposite.
    I would remove and reinstall that connector at both ends.
    So the signal out of the controller is 5 volts. It connects to a stepper driver that drives the stepper motor. Loose wires at to stepper wouldn’t show up as a direction change.
    Most likely the problem is in the pin1 wire.


    Sent from my iPhone using Tapatalk
    Wow!!! You nailed it!!! That precise pin (pin 1 coming out of the controller) was not firmly screwed down, just sort of loosely touching. So I guess heat and vibration over time sort of shook it a bit loose. It's a miracle it worked at all for the past 1.5 years

    Thank you, back in business! And those LEDs will prove helpful for future debugging.

Similar Threads

  1. New G Weike LG900N CO2 Laser purchase thread!
    By mikemccand in forum G.Weike Laser
    Replies: 52
    Last Post: 05-06-2019, 03:54 PM
  2. G.Weike LG900N or LC6090
    By AlanC in forum G.Weike Laser
    Replies: 6
    Last Post: 05-07-2017, 10:56 AM
  3. G Weike LG900N Laser won't fire
    By dasbachc in forum General Laser Engraving / Cutting Machine Discussion
    Replies: 2
    Last Post: 04-07-2017, 04:41 AM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •