Software width/height do not reflect actual cut width/height

In Lightburn I created several patterns that no longer cut to the actual size I have saved in Lightburn. They are consistently 1/8" off. I have performed autofocus at the start of cutting the material. Please advise.

You could take Lightburn out of the equation by setting up a specific step distance in you controller, maybe 300mm, then measuring how far your hardware actually steps by pulsing at both ends of the step and measuring the distance between the dots. Do the same test separately for x and y.

Thank you for the advice. I very new at running Lightburn and the laser, just a few weeks. That process is beyond my capability at the moment. Is there another process I could try first? Does Lightburn have actual tech support?

Yes, we are here to support LightBurn, and ready to assist.

Are you saying that if you draw a square, say 100mm and run that job, the resulting output is different? You say “1/8” off", but that is really not telling us much. Show an example of both what you want to produce, a screenshot of LightBurn, and the resulting cut with some scale for comparison.

Good to know. What do you advise on this issue?

Are you able to do team viewer?

What are your hours for assistance?

The assistance provided to you is thru this forum.

So can anyone answer the question I posted 2 hours ago?

Not without more information from you. This is why I asked. We are here to help, and need you to do the same. :wink:

Since you are tech support what do you need to know. I’ve specifically described the problem to the best of my ability.

Yes, I am saying the output is different than what I have input.

We need to be able to “see” what you are describing.

You show a Boss Laser in your profile, is this a new system? Do you still have access to the support provided when you purchased from the nice folks at Boss? This may be a better approach as they can help you with the entire system.

What is “they”? Is “they” a cut, a fill, a scan of an image? Each could have different issues, potentially requiring a different solution. The “1/8” off" part, what does this mean? The image scan is 1/8" to the left of where you have it on the workspace? Or the cut should be 1" x 1" and it comes out 1.125" x 1.125" or maybe 1/8" smaller, or…?

The details are important. Please share as much as possible to help us ‘see’ what you do, and we can go from there.

A bit of extra testing can narrow the problem down a lot. If the error is always 3mm, no matter what the size of the line cut, that could be backlash (error introduced by change of direction). It could also be motor slip (error introduced by too aggressive head acceleration). If the error is 3mm per 100mm, that’s probably a setup problem calculating steps/mm.

If you cut a square, and allow the head to travel in four different directions cutting it, does the cut line finish at exactly the same point it started?

If you cut a small square, then cut another one twice the size, are they both too small by the same amount, or is the bigger one out by twice as much?

Also, if you cut a 25mm or so circle, is it round, oval, or otherwise distorted?