Silicone cuts with a CO2 with clean, burr-free edges, which is hard to achieve mechanically on such a flexible material. It is the material of gaskets, moulds and technical mats. Careful: only pure silicone is suitable, not filled elastomers.
Settings: what really matters
CO2 only: a diode has no effect on light-coloured silicone. Expect around 70% at 350 mm/min with a 40 W CO2 for 2 mm, in one pass.
The material is flexible and moves: hold it with a frame, magnets or low-tack adhesive. Silicone that shifts by a millimetre mid-cut ruins the part.
For engraving, stay moderate (25% at 2,000 mm/min): silicone melts and partly closes back up, so the design loses definition beyond that.
Common thicknesses and pitfalls
Common thicknesses: 1, 2 and 3 mm sheet. Beyond that, the edge becomes tapered and cutting precision drops.
Pitfall: composition. Many “rubber” sheets sold as silicone are actually neoprene, EPDM or a blend containing chlorine — the latter must be absolutely avoided. Only use silicone whose datasheet you know.
Risks and finishing
Cutting silicone releases abundant white smoke and a lasting smell: powerful extraction is essential. Silicone does not ignite easily, but the smoke saturates a carbon filter quickly.
For finishing, a simple alcohol wipe removes the white deposit on the edges. Silicone cannot be painted and only bonds with a dedicated silicone adhesive.
Every figure on LaserSettings comes with the machine, the laser source, the material and the thickness it was tested on. A setting published for a 10 W diode says nothing about a 40 W CO2, and a setting for 3 mm says nothing about 6 mm: check those four things before you copy any number.
Settings are confirmed or disputed by the members who reproduce them, so reliability comes from cross-checking rather than popularity. Photos of the result — cut edges, engraving shades, scorching — tell you more than a single number found on a forum.
Whatever the material, treat a published setting as a starting point: run a small power/speed test grid on an offcut, clean the lens, redo the focus, work with fume extraction and air assist, wear glasses rated for your wavelength and never leave the machine unattended.