I recently tried cutting some acrylic that appears to glow at the edge when normal room light hits it. My usual cutting grid is a rectangular acrylic ceiling light baffle.
I had no masking on the underside or top surface of the glow acrylic.
It cut real nice however when looking through it, there was a couple places that looked fogged or as if there was oil or liquid on the underside surface. I tried cleaning this off with denatured alcohol and within a minute or two, the edges started to craze/crack. Especially at corners or changes of direction along the edge. Maybe I should have masked both sides or at least the underside...

I assume this oily look happened for two reasons - the acrylic ceiling light baffle doesn't allow smoke and fumes to travel through one square to the next and the fumes may have redeposited on the acrylic. Or it may be the acrylic grid itself that is doing it when it gets cut by the laser.

This brings me to the idea of making a pin table which has been mentioned recently.
So I thought if I could use the laser as a drill and make holes in 1/2 inch MDO plywood, I could just insert finishing nails into the holes, and I'm good to go. Well, not so much with my 30 watt laser.

Making several test holes, I discovered several things.

1. Although tedious, it would be more efficient and the holes will be more uniformly vertical if I did it on a drill press instead. I could mark the hole locations on the board using the laser though.

2. The smallest hole I can get my laser to "cut" rather than engrave, is 0.002.
Smaller and nothing happens.

3. Too slow at too much power and kiss the hole diameter good bye.

4. 40 copies of holes placed on top of each other, and duplicated every 1/2 inch along the X direction does not get processed in such a way that all 40 copies of the first hole get done, then the next hole gets all 40 copies done, etc. Instead, job control does one copy in the first hole, moves to the second hole and does one copy, then to the third, etc. Then it goes back to hole 1 for the second copy. I did not try the "vector sorting" function to see if that would be more efficient.

5. For some reason I could not get job control to cut the holes unless I had black set to engrave even though there was no black being processed. When I had black set to ignore, the red cut holes would not run. I had blue set for positioning, so I could maintain positioning while testing one hole at a time, and later 5 holes at a time.

6. The vector holes will process lots faster than engraved holes.

It was an interesting experiment and I plan to keep at it just to see what else might happen with other variables. It seemed the best holes I got were by doing only 10 to 15 copies at a time all in the same hole. More than that at one time tends to burn out the diameter unpredictably in plywood.

Another observation that was not an observation -
The movement of the laser for a 0.002 diameter cut vector hole is not really even noticeable!