How to Laser Engrave Glass
A laser cannot cut glass, but it can engrave it with a clean frosted mark. Here is how to get it right.
Engraved glassware is one of the best-selling laser products: wine glasses, whisky tumblers, bottles, awards and mirrors. People often search whether a laser cutter can cut glass. It cannot, but engraving is a different story, and with the right method the results look professional.
CO2 vs Diode on Glass
CO2 laser
Glass absorbs the CO2 wavelength well, so a CO2 laser can engrave bare glass directly with a frosted finish.
Use low power and high speed to avoid cracks.
Diode laser
Clear glass is nearly transparent to a diode beam, so the surface must be coated first.
Marking paper, a thin layer of paint or marking spray gives the beam something to absorb.
Step-by-Step Method
- Choose the right glass. Plain soda-lime glass such as bottles and drinking glasses works well. Avoid tempered and lead crystal glass, which can chip or crack.
- Clean the surface. Wipe with alcohol so oils and fingerprints do not affect the mark.
- Prepare the surface if you use a diode. Apply marking paper or a coat of spray and let it dry completely.
- Test on a scrap piece. Start with low power and fast speed, then raise power in small steps until the mark looks even.
- Run and finish. Wash the glass with water, remove the coating and dry it to reveal the engraved design.
Watch: Laser Engrave Glass in 6 Minutes
Watch out for these
- Curved glass such as tumblers needs a rotary attachment for even focus.
- Glass with uneven thickness can crack from heat. Always test first.
- Wear eye protection and keep ventilation running, especially with coatings.
Once you get one glass right, record the settings. Glass jobs repeat well, and a small set of tested settings lets you produce gifts and orders quickly.