It partly depends on whether the sunglasses are glass or polycarbonate. I haven’t tried colored glass yet, so can’t say. I did do some tests on some resin/stabilized burl pieces that were left over from some pen turnings blanks. The results were very uneven dependent upon the color of the resin. Some parts turned dark like they were being burned like wood and others turned whitish gray like they were being etched and some parts were affected very little.
I also ran tests on the 2422 amber acrylic I’m using for my enclosure. Tried the tissue paper test through the acrylic. While the tissue paper was untouched the acrylic was really nicely etched - whether I was focused on the top of acrylic, or on the tissue paper through it.
I guess I’ll have to find some colored glass to play with.
Tried that and it works beautifully. Left is etched through. Right is from the back.
I was really shocked by how good it looked.
I didn’t paint the glass myself, but found some clear glass tiles that had a silver backing. I’m assuming painting the glass would give the same result. The silver looked like normal spray paint but then there was a thicker backing coat. Not sure if you’d need to use something like plasti-dip. Need to lower power a bit to keep from bubbling. Not sure how other colors would react or look.
Depends on what look you’re going for. When you do it this way the glass gets etched. So it’s frosted, not clear.
It looks good with some backlighting but otherwise as seen in above pictures doesn’t really work with the silver at least. Maybe a darker color would help or maybe need to try painting the etched part and see if that helps it pop.