I am new to laser machines so please excuse any obvious or silly comments. I have recently bought the NEJE Max 4 with E80 diode module. I am using LightBurn 1.4.03 on a MacBook Pro with Apple M1, 16 GB RAM, MacOSX Ventura 13.6.2.
The following issue is driving me crazy. The engraving in FILL mode comes out very much skewed to the left on the X-axis. Here is a photo of a test I produced to accompany this post:
(1) The engraving or cutting in LINE mode comes out clean and precise regadless of speed or other settings.
(2) The engraving of a single object in FILL mode, like a single letter also comes out clean and precise (see the letter ‘n’ at the far right). The skewed problem seems to occur when there is a series of letters or objects. I can confirm that the problem also exist when engraving an image.
(3) This test leads me to suspect that this might be a software issue and not a hardware issue, but I am no expert and would take on any advice that you may have.
Having scanned the historical archive of the Lighburn forum, I noticed that this is an issue that was faced by other users in different forms. I followed the advice on all these past discussions and have tried the following remedies but with no avail:
I have tried different engraving speeds (as shown in this test).
I have tried setting the step pin invert to 0 and/or 1 for the Y and X axis (as shown in this test).
I have checked that the axis steps are as per the manufacturer and that the X steps are the same as the Y steps.
I have checked the belts in all axes and they are tight. I only got this machine 3 weeks ago.
I have uninstalled and installed back again Lightburn.
I have removed and reinstalled back again the Device.
I do not have a CO2 laser so the PWM Rising Edge fix does not apply to my device.
I also attach screenshots of my device settings and machine settings below in case these can help identify the issue.
I have tried with speeds 3000 and 600 mm/min and the result is the same (I did not attempt the intermediate 1200 mm/min because it seems hopeless). Here is the photo:
The Y axis runs on rollers and moves smoothly. When I raise the bed in 45 degrees it falls by itself is a smooth manner.
The Neje Max 4 X axis moves on a rail and comes pre-assembled from the factory. The belt is fixed and cannot be adjusted. Having said that, the X axis feels much more rigid and when I move it by hand it does not run very smoothly. I do not know if that is because it runs a rail and not rollers.
UPDATE: Here is a Google drive link below with a video showing how the X axis runs smoothly, but the Y axis not. Please raise the volume in the video to hear how the Y axis movement is not so smooth, it is as if there are obstacles. I do not know if this is because it runs a rail and not rollers. It might be normal, but it would be good to have a more experience opinion on this from others with similar laser set ups.
Good observation! You are right to say that it is even more skewed in slower speeds. I will now try the Offset Fill mode and post an update soon.
Here is the update: OFFSET FILL works! It is not a spectacular result but it seems to align reasonably well. However, I noticed that the rectangle outline, which was the layer that was done last, had shifted to the left. When I looked more closely I also noticed that the “title” on top of the letter “j” (the dot) was more to the right than the rest of the letter “j” (see the red circle in the photo). This is because the “title” was engraved first, then the X-axis shifted to the left and did the rest of the layer.
This behaviour of shifting has inspired me to do more testing on how the X-axis shifts to the left, and I will post an update on this in a few minutes.
The second test I did was in relation to framing. I created a ruler of 10cm and framed the laser again and again. I made a video that shows how each time the laser frames shifts about 0.5cm to the left. There is evidently and problem with the X axis. I cannot upload a video in the forum, but here is a share link from Google Drive. Please let me know if you cannot access it and how it is best to share videos for you:
Thanks for the advice. I have tried switching on and off the bi-directional fill and there is no change in the result. It is a good idea to change the scan angle to 90 degrees and will try this soon.
My apologies for the late response. I made a test using different scanning angles. In the photo below, the numbers on the left indicate different scanning angles. The text “neje” was supposed to be perfectly aligned in a column, so the misalignment indicates a problem of framing and engraving.
On the bottom of the photo, I engraved the longer text “Marin & Titouan” with angle 90 degrees and with angle 0 degrees . The 90 degrees angle result is ok but the 0 degrees angle again creates the messed-up skewed result.
Also, compare the two texts “neje” and “Marin & Titouan” with 0 angle engraving. The shorter text “neje” is a little bit skewed but the the much longer text of “Marin & Titouan” is very much skewed. I have confirmed this with other text, and it holds that the longer the scanned layer the more skewed is the result.
That’s interesting that the 90 degree scan works without issue. I’m going to assume this isn’t an issue with step signal. But can you confirm that you have not changed any of the stepper motors on the machine?
Can you try 2 things:
Dramatically lower the acceleration setting for X axis to see if that makes a difference. $120=50
Can you generate the gcode for the test using File->Save Gcode, save with .txt extension and then upload here?
I confirm that I have not changed any step motors. The machine is only 3 weeks old. I will try your suggestions later today and post an update. thanks!
