Well Aligned Laser
From now on, I will be running an alignment and beam quality check before all stencil cut jobs. This will give me some correlation between cut quality and laser status. If I see that the alignment and or beam quality is too low, then I will do a laser tune up before running a cut job.
The check will consist of a beam pulse on triple layered painter's tape on the gantry mirror opening. The positions will be each corner, the center and then again a second pass of left/right-back and left/right front. Those last two will keep the same tape target for two pulses to check beam spot overlap (the more overlap the better).
As you can see from the photos, the laser is in a very good status. Indeed, in the 15 months I've been using the 4 inch focal length laser, I've never seen such highly symmetric beam cross sections and so well aligned on each other (and relative to the center point of the mirror.)
Before running the laser status check test, I thoroughly vacuumed and wiped down the inside and outside surfaces of the laser system, including the surrounding floor, chiller, the accordian exhaust vent tubes and the compressor (the blades were not cleaned by me this time).
Here is what a clean laser system looks like: