After playing a while with my "Quick, dirty and cheap laser engraver" (see my instructable with that name) I experimented with other materials and really like to engrave glass. And it turns out to be fairly simple to do. Even with a 2 Watt blue laser. The picture shows the result of my second attempt. This little instructable shows you how I did that.
Step 1: Make Preparations
First of all you have to figure out where the engraving takes place on the glass (I dry run with the laser on low power while the glass plate is in place) and make that area black with a felt pen or something similar.
The dry run:
With help of the program UniversalGcodeSender that I use in my projects you can move the laser (low power setting, not burning) around the glass plate and on the pc screen you can see if you are covering the whole picture.
Step 2: Check the Black Covering
You have to cover the whole area with no spaces, like the picture, otherwise you can get interruptions in your engraving.
Step 3: Engrave
After you colored the desired area black you place the glass exactly on the same spot. To be sure, you can dry run again, see step 1. If all is ok, you can power up the laser and start engraving. The laser must travel really slow (the instructable logo takes me more then 12 minutes to engrave with my 2 Watt laser) to engrave glass.
If you listen carefully while engraving, you can hear the glass crinkle!
After the engraving is ready you can remove any glass flakes with sticky tape. Please see also my video.
Step 4: Mirrors
Mirrors are really nice to engrave. The result is fairly stunning. For my nephew's birthday I made the mirror above, it turns out very nice. The holes you see are holes in the plastic wrapping, they are created as a side effect when the laser shines through the mirror. After removing the wrapping there is a crispy clear image.
You have to do all the previous steps with the difference that you have to do them on de back side of the mirror (don't forget to flip the image horizontally). After you engrave the mirror there is no need to remove the ink, but it's advisable to seal the back side to prevent the aluminum to oxidate. I used spray-plastic.
I hope this instructable will inspire you to be creative with glass/mirrors and a laser engraver.