Engraving Sandstone with a Diode Laser

(Looks like this question was never actually answered back in Dec. '20.) Does anyone have experience engraving sandstone coasters with a diode laser? Recommendations?

Lol. Just this weekend I was looking at the thirstystone coaster next to me and wondered the same thing. Actually considered trying it, but they are old and stained. Figured it wouldn’t be a fair test.

My son has some that are monogrammed and look like it was done by laser but the detail was such that I figured it was done on a galvo.

What would be the results of lasing sandstone?

I would think it would be hard to even see. I do it on slate, but have never even though about sandstone as being a viable medium.

Please post some results …

:smile_cat:

I did a quick test before work. Genuine thirstystone, well used, 20W diode. It marked, but not real dark. I didn’t run a conventional material test as I didn’t want to stare at it in my coaster. Lol. I did some concentric circles at a few different power settings. Lower power was better. 1500mm/min and 80-20%. 20% is where I said “that’s pretty good”, and did a filled capital letter G. It’s visible, but not great. Very quick test, as I said. Definitely not definitive, but I don’t think diode can produce good results without a catalyst of some type.

I washed one and will let it dry overnight, then I will apply some Brilliance black in the morning and see what happens. I don’t have any TiO2, but I suspect that would work OK if mixed with water. Something that would wash off easily.

I know sandstone and thirstystone aren’t exactly the same, but it’s what I have, and probably close enough to be representative.

Some materials just won’t mark… I suspect these are in that group.

:smile_cat:

Remember, this coaster is quite a few years old. I scrubbed it good with soap and a stiff brush, but couldn’t get out all the stains.

I used the same setting as I use for Brilliance on Stainless. Nothing saying that’s ideal. I just figured it was close enough for a proof of concept.

That said, with Brilliance, before rinsing…

…and after (still damp). I scrubbed it aggressively with soap and a stiff nylon bristle brush.