Originally Posted by
omgwtfkthx
Searched through the forum about this beam splitting/halo/ghosting effect but all answers are basically check your alignment.
tldr: why is my laser doing a halo cut when my alignment seems okay?
I'm building my own laser and have been trying to tackle what I assume is an alignment issue for a while now. I sometimes get a double cut halo as if the laser beam is splitting and I can't find the cause. The first image shows that after doing a basic mirror alignment my beam is mostly hitting the same spot at all four corners of my gantry. I also checked the vertical alignment on the last mirror. I used a laser level to ensure my gantry has an even height across both axis. I used the same laser level to ensure the tube itself is also properly horizontal. I used a speed square to ensure the gantry and laser tube are spaced correctly. Checked the lens for deformations but found nothing. Secured mirrors to make sure they aren't vibrating. Ensured the cutting bed was level.
The thing is, I've repeated these steps over a dozen times, aligned/reset/aligned again, fixing things, making my four corner alignment tighter along the way. But this halo cut won't go away. What am I missing?
Removing the nozzle shows the issue more clearly.