Raw ABS — the material of 3D prints, enclosures and technical sheets — must not be laser-cut. It does not vaporise: it melts, sticks and gives off acrid, toxic fumes.
What actually happens
Heated by the beam, ABS depolymerises and releases styrene and hydrogen cyanide, plus very fine particles. Styrene is a recognised irritant and hydrogen cyanide is acutely toxic: even in small amounts, that is not an acceptable exposure in a home workshop.
Technically the result is bad anyway: the edge melts into a sticky bead, the material re-welds behind the beam, and the part warps. No power / speed combination changes that.
The greasy soot released settles on the lens and rails, with a smell that lingers in the machine for days.
The exception and the alternatives
There is one important exception: two-ply engraving plates sold as "laserable" (Gravoply type) are formulated for it and engrave very well. Only the surface layer is removed, not the bulk plastic.
For cutting a plastic sheet, cast acrylic gives a crisp polished edge, and polypropylene suits a flexible part.
For an existing ABS part, use a router, a saw or a knife: ABS machines very well mechanically.
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.