I’ve bought a company, one of the laser cutters that I’ve acquired is Chinese manufactured 8" x 4" flat bed with a Ruida RDG6332M controller, I’ve spent this week cleaning it up, replacing all the mirrors and the lens, the laser is firing, I’ve lined up the mirrors and the lens so that I’m getting the probe and the laser hitting the target material (5mm acrylic). The z axis is set at 3000mm which I’ve read is that default limit. The jogging on the console doesn’t move the z-axis and it also doesn’t move from Lightburn. It’s enabled in the device settings. My current plan is to change the stepper motor and to clean the z-axis rails. (the whole thing is covered in gunk). I doubt the stepper is actually faulty. Anyway my question is, is it more likely something with the configuration? If anyone has some suggestions i’d be grateful as i’m a bit stuck!
Just for scale, we’ll assume you mean “feet” rather than “inches”.
Because the Z axis doesn’t move when commanded from the machine console, LightBurn and its settings have nothing to do with the problem. You can use LightBurn to change the Machine Settings, but until the controller can move the hardware, LightBurn will also be unable to move it.
Because the Z axis cannot home, the controller sets the position to 3000 mm.
Are you certain the Z axis drive is a stepper motor, rather than an AC motor? If the machine has separate up/down buttons (not on the controller, maybe hidden on the side) to control the Z axis, then it’s intended for manual control with an AC motor and the controller will be unable to do anything with it.
Find the driver for the Z axis motor and upload a picture of the data plate on the flat side and a picture of the DIP switch settings so we can see what you’ve got yourself into. Tracing the wires from the motor to the driver will help; if the wires don’t end in a stepper driver, then it’s an AC motor.
Take a screen shot (not a phone picture) of the Z axis Machine Settings in LightBurn to show the status quo.
Assuming that was the case, then the problem lies inside the machine and LightBurn has nothing to do with it.
The switch settings look plausible:
2.1 A
Half-current hold
4000 step/rev
However, given the size of the machine, I find it hard to believe a single stepper set to 2.1 A can lift the platform:
What does the Z axis drive train look like?
Is there a smaller Z axis moving just the laser head?
Ruida controllers sometimes drive the platform motor with the U axis, rather than the Z axis, so perhaps the Z axis is (weirdly) dedicated to something like a rotary.
While you have your head in there, trace the wires from whatever motor moves the platform back to its driver brick. If they end up at a different driver, that’s a hint.
You gotta take it apart and clean All The Things with toxic chemicals, particularly the linear bearings. Conversely, the laser head looks suspiciously new, even if the Mirror 3 alignment knobs & screws are strictly junk-box jank.
Those two grubby microswitches should be the Z+ and Z- limit / home switches. Check the controller’s diagnostic display to see which signals, if any, they correspond to: an input bit should change when you trip them by hand.
What is the mystery box with the (disconnected) SMA cable supposed to do? Whatever it was doing, it isn’t any more, which may account for some of the “not moving” problem.
