It took about a dozen tests but I’m finally getting good consistent results on shot glasses.
A year ago, I designed a jig to hold 20 shot glasses for engraving (Shot Glass Jig & Template). Within a couple days of getting my Glowforge, I cut a 1-glass version of the jig to make sure it would work as intended. It didn’t. It was close but needed a few tweaks.
With the 1-glass jig perfected, I started seeing what I could do with it. Based on information on these forums, I experimented with a wet paper towel over the glass and, today, with a thin layer of dish soap. With wet paper towels, I was getting inconsistent results likely due to the towel drying out before the engrave finished. I thought for sure that would be a problem with a 20-glass jig. My one test with neither a wet paper towel or soap resulted in a cracked glass. Don’t try this at home.
Today I got five good consistent engraves using dish soap over the glass. Just in time for a trip to the consignment store that has been asking me for shot glasses for over a year. Time for Goldfinger to start paying its way.