I have a Chinese red and black 100W Vevor laser engraver and I’m having problems at startup when the controller is setting the origin.
The head moves on the X axis until the proximity sensor lights up, the corresponding led lights up on the controller but the X axis motor doesn’t stop and the head keeps going and bangs repeatedly against the edge of the frame.
I’ve tested the proximity sensor with a piece of metal, it lights up and the corresponding LED on the controller as well.
Most likely, the wire from the sensor isn’t making it all the way to the controller’s input terminal, so the controller has no idea what’s going on out there.
The controller panel on the machine will (uh, should)
have a diagnostic display showing the input states:
When you figure out which menu sequence produces a similar display on your machine, you can see how that sensor appears to the controller.
We’ve had a couple of cases where the sensor is correctly wired to the controller input, the input is being pulled low when the sensor is active, but the controller’s status display remains inactive. The only resolution is a new controller, because the input circuitry is defective.
Still, as I press reset or restart the machine it doesn’t stop on the X axis while passing the proximity sensor…
Is there a way to manually set the zero ? As a temporary fix I’d like to just Esc the zeroing at startup, position the head in the corner and manually set the position as 0,0 in the controller.
Is the sensor lighting up the X- indicator, not the X+ indicator?
If the sensor is on the correct input, then we know several things:
The controller has homing enabled
It is homing in the correct direction
The sensor activates with the laser head nearby
The controller sees the sensor activation
It ignores that input and does not home successfully
Which suggests the controller is defective. IIRC, @jkwilborn has one with the same symptoms on a different input pin.
You can disable homing for the X axis, but AFAICT there is no way to tell the controller “This position is home” and force that coordinate to be 0.
My KT322N controller sets the current position of an un-homed axis to 10000. When LightBurn tells the controller to move to a specific absolute coordinate, the controller assumes the axis is really at 10000, not its actual position, and smashes the laser head into the side of the platform on its way to the commanded position.
Hilarity ensues.
There may be a way to use relative coordinates, but IMO that would be absurdly fragile and prone to exciting failures.
If this is a new machine and some shred of warranty exists, you’ve got a pretty good claim. Otherwise, the controller is just another replaceable part.
It’s lighting up the Xlimit-.
As you can see in the picture, my controller also sets the position to 10000 when un-homed.
Well, I guess I’m good to buy a new controller
It would be really convenient to just be able to set the home position by pressing a button…
So… I’ve just noticed that as my head is moving toward the back the controller loses the signal from the sensor while the sensor itself remains lit!
I might just have a faulty cable on the sensor!
I changed the sensor and everything works fine.
Turns out the cable was indeed faulty but only when straight. The controller was losing the signal add the head was moving toward the back of the machine.
With the benefit of hindsight, how could we have gotten from your initial observation:
To the resolution:
Without grinding through all the other possibilities?
One test I assumed wasn’t necessary: verifying the controller’s sensor input was active at the home position, not at another, more convenient location elsewhere along the axis.
Gotta remember that for the next time.
Thanks for reporting the actual solution, because nobody would believe it otherwise …
