This is primarily a youtube video, but I’ve copied the description here in case youtube catches fire, or for easier reference, or something. https://youtu.be/XgNtlAwLSBs

After watching this video on cutting sheet metal with a diode laser ( https://www.youtube.com/watch?v=GHFWKfaUeuU ), I ended up buying one. (An Ikier K1 Pro Max 70W, I mean.) I did get the sheet metal thing to work (with like 3 pancake air compressors, 5 cf/m each, daisy chained to provide 50 PSI (after the water condenser) without overheating). I also have been experimenting with scoring glass, to break into shapes for stained glass. Here are the settings I’ve found to be pretty good. I don’t know which of these are actually necessary; experiment and find out, if you want. Note that my first attempt (red glass) went as slow as the laser could go, which both cut through the glass in several places, as well as caused several large stray cracks.

Common to all:
50 PSI air as described above.
Set something on the edge of the glass to keep it from moving from the air.
10 seconds pause between each pass to cool off.
Autofocused.

Red transparent glass:
I just consulted my notes, and it seems that I misremembered – the settings I thought I dialed in on red glass were instead dialed in on the purple glass below. From the watermelon test (see end of video), it seems the red glass might need a little slower (-20%?) than the purple, or a few more passes.

Dark purple transparent glass:
1 pass 50mm/s, 5 passes 100mm/s.

Deep green transparent glass:
10 passes 50mm/s. This is probably a little too much – I got score penetration ~1/3 the thickness of the glass, and it cracked the glass (but off the ends of the shape I cared about out to the outer edge, so it didn’t much matter).

Plain clear glass:
6 passes 50mm/s, painting with red layout fluid before each pass. (I also got a success using a sharpie, but it was hard not to move the glass when drawing on it. Failed with printer ink applied via syringe.)

Lemme know if you want the failure logs, too.

Here’s the more specific of the supplies I used; if not listed, searching Amazon is probably fine. (Also probably fine even if it IS listed, but the exact settings are less likely to be right.)
Colored glass: https://www.amazon.com/gp/product/B0BXB88LGN
Plain clear glass: https://www.amazon.com/gp/product/B093PFTVCN
Red layout fluid: https://www.amazon.com/gp/product/B007464BQM