Hello, I am new to light burn and get a distortion when trying to make a simple box with boxes.
have you checked the length of move of the axis?
On a new LB design make 1 line on X of 50mm and one on Y, same distance then engrave, take a ruler and check if lines are both of 50mm, if not you have to calibrate axis.
You screens are flipped around because you have either the software and/or the device incorrectly configured. Generally you probably didn’t setup Lightburn properly.
I’d check the home position in the ‘Edit → Device Settings’, but you missed something somewhere…
You should also go to ‘Edit → Machine Settings’ and save your ‘factory configuration’ if you have not done so already.
Good luck…
Thanks for your reply, I thought the XYZ calibration settings are stored on my Arduino (steps per inch or mm). I’ll try your test. What doesn’t make sense though is the first end of the box in the upper left corner of the photo came out OK. Why?
Did you make this box, or did you generate it via one of the on-line applications?
The failure appears to occur in the red circle. The top of the cut, looks like the correct position, but it’s long enough to almost line up with the bottom of the left side part. At the red line, it’s at the correct position? The bottom of the piece actually lines up to the smaller part on the left. So it got ‘streached’ somewhere here.
All the ‘green’ was where you can see there is an issue.
This is the Y axes. Because there is no .lbrn2 file to examine, I had to make assumptions. Such that the holes were cut first, but have no idea about how the objects are cut out.
You can set a ‘lead in’ to help reduce the burn where you enter the object.
You can see how it causes the laser to start in a scrap area…
I would check your acceleration and speed settings, as it looks like your Y axis motor is slipping (losing steps) during the cut.
Hi Kilrob, thanks for the advice I think I found the problem if you look at the
The first line looks correct - It appears that the laser started where the ‘tail’ is on the upper part of the picture, and moved upward, turned right, moved across, turned right again, moved down, missed some steps along the way, then turned right one last time to complete the square. The 3rd line is the one with missing steps.
Thanks Jack, you’re right the Y axis somehow is out of calibration. You can see my latest post I did a 50 mm² and the X axis was perfect but the Y axis was 5 mm short of 50.
Thanks for the help, Carl
If you are correct, I’d expect the corners here to be 90 deg, but they don’t appear to be.
Are line segments a and b the same?
It visually looks ‘off’…
even if you use arduino is always a GRBL, in LB under machine settings there is a button called axis calibration
This doesn’t seem like a Y-Axis calibration issue. in the square test the top line looks like it could be close to the 50mm. Only the bottom line is incorrect. If this was about calibration I would expect both lines to be off by the same amount.
This seems like a stepper missing steps issue. What speed and acceleration is this being run at?
Hello Kilrob, I checked my Y axis
Hello everyone, I think you much for all the help you’ve been giving me, thank you
Please check my previous reply.
Also, can you share the DXF file here? Someone can review to confirm your suspicion.
Can you post what your GRBL settings are for acceleration for the X & Y axis?
@Cjsolar Loose grub screw on the Y axis motor pulley?
Did you try a different speed? To me it looks like missed steps. Maybe the speed or acceleration is to high.
Thanks for your help. Last night I checked the Y access again with a metric rule @ 250mm. I traversed the Y access several times and it was completely repeatable every single time. My XYZ table is homemade. My X access is powered by a five phase stepper motor which is then hooked up to a planetary gear reducer for even more accuracy. My Y axis is powered by a Nema 23 and is also attached to a planetary gear reducer. What doesn’t make any sense is how can that be accurate when testing the Y axis but can’t accurately cut a square with fingers which is 50mm X and 40mm Y.
In this second picture I designed the cut out with the fusion 360 and you can see the Y access is short. This was not cut with Lightburn. The file was generated by fusion 360 into a GRBl.nc file.
I forgot to mention my cutting speed is 86 mm/Min. Not very fast.I have since then ordered a new stepper motor driver to see if that’s the problem. Maybe there’s some corruption in my Arduino Uno
Again thank you everyone for your help, Carl
