CO2 laser alignment beam issues

The problem is that in one corner of the table the beam runs diagonally to the right, it looks like this:

About two days ago I was cleaning the optics and after finishing setting the mirrors something touched me and I checked if the beam falls properly in each corner of the table - the effect above.
I checked the perpendicularity, parallelism of x to y and the tube relative to the axis and I found nothing, I dismantled the mirrors, the tube and set it from scratch, I rotated the tube around its axis because I thought maybe the lens in the tube is crooked, but nothing brought any results.
Has anyone had a similar issue?


The only fix I know of is a very small adjustment to m1… I’ve never had the issue… so I haven’t personally done it…

About 33 minutes into this alignment video, Russ mentions how to check and correct this. He’s usually correct.

It’s a very good video… I suggest you watch the whole thing…

Good luck


Thanks for the reply, interesting material. I borrowed more accurate measuring instruments from work and it turned out that my frame is not square. The corner at point 1 was 0.8mm higher than the others and the angle between y and x was less than 1 degree. I haven’t fixed it yet, so I don’t know what the results will be, but as soon as I do, I’ll write if it solves the problem.

If you can correct his, more power to you… most of us can’t measure anything with any useful accuracy…

Even if I did, I don’t know how I could change most of my machine as it’s welded together. The pretty much eliminates me fixing it.

Did you try the 4th corner fix from Sadler?

I doubt most of our lasers are any more/less square than yours… I don’t know if it’s worth the trouble is you can handle it with an m1 adjustment…

Please let us know…


I tried to fix it with m1 adjustment, but it didn’t give me any results.

I made laser myself, so I can do fix . At the moment it looks like this:

The beam in the 2nd corner still escapes a bit but the improvement is huge. I think I will leave it as is. All I had left to do was center everything and check the correctness of the cut. Btw, I’m very happy with the results.

Was this corrected to this by m1?

Doubt it will ever be an issue…


When I tried to fix on m1 I got something like an x ​​pattern made of dots, unfortunately I don’t have any picture.

Correction is done by frame alignment.

I raised the corners 2, 3 and 4 by 0.9mm and this correct beam vertically, horizontally it was a bit harder I had to stretch the frame at point 1 to the left, result - picture above.

I’d suggest you lower the power on your test spots, it will be much easier to see and diagnose…

This is two shots on Y axes mirror…

Good luck