glass and lasers

he recipe is easy: two parts white PVA glue, one part water, and two parts powdered titanium dioxide. The TiO2 is the important part; it changes color when heated by the laser, forming a deep black line that adheres to the surface of the glass. The glue is just there as a binder to keep the TiO2 from being blasted away by the air assist, and the water thins out the goop for easy spreading with a paintbrush. Apply one or two coats, let it dry, and blast away. Vector files work better than raster files, and you’ll probably have to play with settings to get optimal results.

This is a well-known technique for laser etching metal, although this is the first time I’ve seen it used with glass.

You can use molybdenum spray lubricant, available at the local auto parts store, to laser etch metal. The molybdenum sinters into the metal and leaves behind a nice gray “mark”. Use this to put your logo on metal parts that you make.

Spray lubricant might work on glass as well. You might also try titanium spray paint.

A potential problem with experimenting on glass is that the heat of the laser tends to crack the glass. If this happens, try using less power and/or faster speeds.

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but you can absolutely engrave glass without the special coating on a CO2 laser. . A wet piece of newsprint over the material to reduce excess chipping, and the laser leaves very nice marks where it fractured small chips free under the sudden heat. Certain kinds of tempered glass don’t work neatly with this, but I’ve run hundreds of bottles and cups and things like that.

To the best of my knowledge, this doesn’t work with a diode laser, but the article specifically mentions he has a CO2 machine.

Using glass frit (the finer the better) may also work when combined with a binder/sticking agent. I’ve tried it without and (if you turn off/away the air assist) it can melt/sinter the colour to the enamel of a glazed tile.
But the price of enameled tile itself is so low this technique only makes sense to customise tiles.
Perhaps a modern version of stained glass windows?

crylics absolutely DO work. I use white acrylic craft paint to get black markings on glass and tile and I use black acrylic craft paint to get white markings on glass. Been doing that for several years now with absolutely beautiful; results on both a 5w as well as a 20w.