When a tube lases, it has to resonate properly with the beam going back and forth… As the tube ages, which can occur suddenly, it no longer resonates properly and produces other patters in the beam indicating a gas problem…
All you are doing is looking at the resultant burn to see if the output is a Gaussian type power curve… although too dark the idea is to have a TEM00 nothing else… this is worst case…
This is a graph of proper power distribution… it should be darker in the center as this is where the most energy exists in the beam.
These are the TEM00 state and a failure… it can be many patterns, we want the TEM00 type output… It’s really a bit dark, so I’d go for less pulse time or duration.
This is when mine failed…
The correction in this is usually a tube replacement 
Check it and see what you get… post a photo of the results for us to examine.
Alignment required you to move m2 repeatably until the burn spots coincide.
Did you move m1 to be as centered as possible on m2 when they are as close as possible?
IR from a co2 is not visible… wouldn’t expect it … if you mean something else, please explain.
I think it’s not aligned correctly… until we determine if it’s resonating, It sound rather like you’re just having an issue with alignment…
Let me know what you get from m1 test.
If all else fails, try moving the mark onto m2 via m1’s adjustment when it’s max distance from m1 and see how it looks when you bring m2 to it’s closest position.
Did you move the physical mount of m1 or did you just use the knobs for adjusting?
