I am using Lightburn Version 1.3 on a Jtech 24W Diode Laser attached to a shapeoko hobby cnc machine. My computer is a MacBook Pro. When I first got the machine I test cut small shapes without issue (about 5 weeks ago). I began having issues with “tabs” showing up in my workpiece. This has gotten worse as now I cannot cut out a simple circular or rectangular shape without there being large tabs that hold my workpiece. I have checked the settings and the “tab/bridge” option is turned OFF yet I still get these points where the laser beam stops. There is no burn attempt at all on these points. The latest one I tried was a small rectangle measuring 5.5x.75 inches. The laser stops altogether when it gets to the bottom left corner and turns back on when it gets to the top of the shape. there is a small tab at the bottom right of the shape on the other side about 1/8" in size. Is this an issue anyone else has had to deal with? I have tried different power levels, shape sizes etc but the tabs are there just proportional to the shape size. Any ideas? Thank You in advance.
Based on what we saw from the last cycle looking at this the issue is almost certainly with the hardware.
Do you have a meter that you can use to test voltages? I’d suggest testing for PWM signal out of the Shapeoko. If you can confirm that the controller is requesting laser on then you know the issue is downstream of that. Either in the Jtech interface or the laser module or in the wiring connecting the components. If you can see that the PWM shows laser off during the gap periods then you know the controller is not sending the right signals.
I added a quick text to a blank file and ran it at different speeds. At higher speeds there are no tabs (60ipm at 50%) but when I slowed it down to 10ipm and 90%power the tabs returned. Very frustrating.
If you’re getting different behavior at different speeds then sounds like this is entirely from dynamic power controls from your controller. Or it’s possible that your laser module is falling off below certain power thresholds.
Let’s just the basics.
Can you run these commands in Console and return output?
