I have searched and read and watched an ungodly amount of media in regards to the aiming of CO2 lasers. I believe I am heading down the right path.
I fear I have a twisted gantry or frame causing low power cut through issues.
Why I believe this is that I can cut a materials card test card out of 3 mm baltic birch in the upper right section of the bed and get items the results I’m expecting.
I can cut super tight lines (1 mm wide left after cut) through with complete drop out and no pieces hanging on, just lift the sheet and everything is left on the bed.
But only on 3/4’s of the bed. My front right corner will not cut through at the same settings as the top left corner.
I have spent close to four days @ 6-8 hours learning and adjusting and reading and adjusting and watching and adjusting and nothing seems to cure it except raising power or lowering speed, of course this leaves me with differing results from one corner to the other on the diagonal.
When performing the alignment I can get what I would call 95% perfect overlay on my marks on the 2 -3 mirror setup when traversing the x axis from left to right at the rear of the bed and also at the fore of the bed.
When I check the marking at rear left to front right the are only 75 to 80% overlay.
Photos, hopefully, below.
The wisdom of the giants would be appreciated so I can stand on your shoulders…
Good morning, until the “giants” have come up from their beds, I will prepare a little for them.
First, make sure your tube is OK, with the appearance of the picture of your M1 it can’t be judged, try with less power and or short pulse time to get a light brown marking of your laser beam.
Without wanting to make you sad, but M2 is not in center. I know it can be hard to hit the middle perfect some time and that some giants (?) think it’s not the most important thing, just near and far hit each other … I want them in center on M2 and that of course, also applies to M1 and M3.
You also need to remember to check if your nozzle is perpendicular, there are many who forget this step.
Last, but you’ve probably already checked it is whether your machine bed has the same distance from the nozzle over the entire machine bed.
Agreed, except for m3. It may not be centered on m3 as head Z movement determine X axes alignment down the tube and Y adjustment (from m2) determines Y axes position of the beam in the tube. If it doesn’t go down the center of the tube, the beam will not be vertical after it comes out of the lens.
Lighten up on the burn time so we can see the power across the spot.
You may not have adjustments on the head or m2, so you’ll have to do the best you can.
The head that came with my machine, as you can see, the hole isn’t centered over it’s own mirror or the down tube where the lens is mounted.
Sometimes you can correct the 4th corner anomaly by adjusting m1. It’s very touchy and you don’t want to disturb the alignment with the other mirrors, so a very, very, very slight adjustment is all that’s required.
@bernd.dk - Definitely agree that my points are not centered but after reviewing all the various guides it wasn’t totally clear whether that was a necessity or a nice to have. Will now try to center everything as well.
I should have assumed otherwise but the drive to make things versus fiddle with trying to achieve perfection got the better of me.
@jkwilborn - Thanks, I believe I read through one of your other posts to another poor soul that ended up finding the issue to be that the laser head itself was cattywampus on the Y axis.
I sincerely appreciate the assistance and will be puttering away at it again today and should be able to update in a while.
When we suggest things, we have to make assumptions and you know how that goes.
With any engraver like these, they need to be square in all 3 dimensions. Since most of the rails or internal frame is built using jigs to ensure they are square, it’s unlikely that the frame is bent, although it happens. How I can’t imagine.
When it comes to the head there is lots of ways it can be off, but we usually consider other adjustments first. Head being square should have been brought up in one or more of the videos you’ve watched.
Also as recommended by another and it makes sense to me, request was to check and set alignment on LH front and Rear and then see is RH front and rear align.
Results were that LH F and R can be aligned and that makes RH Front and Rear align but LH and RH are different by, you guessed it, 3mm.
I’m a little surprised that you can get the relatively nice result that you see in the last picture (if I understand it correctly). It shouldn’t be possible with a 3mm deviation from the squareness.
I would still like to see a clearer picture of your laser beam on M1, not as a burned-out black spot but as a brown round filled circle.
It will be interesting what OMT servis can do about your problem.
