This page describes a laser engraving setting published for Miroir (dos gravé) at 3 mm, tested on a Gravotech LS100 Energy fitted with a CO2 25W source (10,600 nm CO2, 25 W). It states the exact machine, source, material, thickness and operation of the test; power, speed and number of passes are shown with a Premium pass.
Why those four facts matter: a engraving setting that works on Miroir (dos gravé) at 3 mm does not transfer to another thickness, nor to another source. A 10,600 nm CO2 rated 25 W does not deposit the same energy as a stronger module, and the speed has to be adjusted accordingly. Copying a number without checking those four points is the first cause of a ruined part.
Published by LaserSettings (estimation). No other workshop has confirmed it yet: treat it as a starting point, and confirm it from your account if you reproduce it.
No photo comes with this setting yet. If you reproduce it, publish yours from your account: a picture of the result is worth more than a line of numbers.
Recommended routine before running the part: clean the lens, redo the focus, engrave a small test grid on an offcut of the same Miroir (dos gravé), then adjust the speed rather than the power. Work with fume extraction and air assist, wear glasses rated for 10,600 nm CO2, and never leave the machine unattended.
Gravotech (Gravograph) comes from mechanical and industrial engraving and offers CO2, fibre and UV solutions, often integrated into a production line. On these machines the setting is part of a documented process: the useful value is the one validated with the same optics and the same certified material.
A mirror is laser engraved from the back: the beam attacks the silvering layer, which disappears where it passes. The design then shows through when seen from the front, with a sharpness that engraving the glass itself cannot match.
CO2 only, around 45% at 1,200 mm/min with a 40 W CO2, artwork mirrored in software since you engrave from the back.
Do not aim to engrave deep: the goal is to remove the protective paint and the silvering, not to bite into the glass. Excess power chips the front face.
300 dpi is enough: beyond that, pulses overlap and the layer peels off in patches instead of disappearing cleanly.
Common thicknesses: 3 and 4 mm. Mirror is not laser cut: have it cut to size by a glazier before engraving.
Pitfall: the front face. A mirror laid face down on the bed scratches on the slightest speck of dust. Rest it on a soft cloth or a clean foam sheet.
On some mirrors, a thick protective paint covers the silvering: two passes are then needed, the first removing the paint, the second the silvering.