How can I keep glass from chipping or flaking when laser engraving?

[Gene Uselman]

Another article from Awards, engraving and Personalized.......

How can I keep glass from chipping or flaking when laser engraving?
October 31, 2019
Answer

When a laser strikes glass, it fractures the surface, but it will not engrave deeply or remove material. The fracturing of the glass surface produces a frosted appearance but can cause roughness and chipping depending on the type of glass being engraved. While the frosted appearance is desired, the roughness and chipping are not.

To produce a smooth, frosted finish, here are some tips:

300 DPI: Using a lower resolution, around 300 DPI, produces a better result on glass as you separate the dots you are engraving.
80% grayscale: Change the black in your graphic to 80% black to further separate the dots for less micro-fracturing.
Jarvis dithering: Running with a Jarvis dithering pattern in the driver (you’ll find this under the raster speed and power settings) randomizes the separated dots for a smooth look when engraved.
Masking: Some people find that applying a thin, wet sheet of newspaper or paper towel a little larger than the engraving area also helps with heat dissipation and improves the engraving. Just be sure that there are no wrinkles in the paper after it is applied.
Dish soap: Using your finger or a paper towel, apply a thin coat of liquid dish soap – any kind will do – over the area to be engraved. This dissipates the heat when engraving.
Polish: If there are small shards of glass, you can polish the area with a Scotch rite pad or something similar.

[Ian Bell]

Great advise, always handy to have these tips and tricks available.

[Gene Uselman]

How ya coming on that Rotary, Ian? I kinda forgot about you.

[Dejan Mandelc]

From my experience, a have got the best result when:

I make background black (when u invert in RD works it is white ).... resolution dithering and interval by Russ formula.... and power as low as possible ...

For me this settings was the best ....