Walnut is the premium wood of laser engraving: dark, dense, with an elegant grain. Its quirk is counter-intuitive — the darker the wood, the more carefully engraving must be planned to stay legible.
Settings: what really matters
On already dark brown wood, a burnt engraving adds no contrast: it disappears. The right approach is to engrave deeper and wider to create relief and shadow contrast, or conversely very lightly for a satin effect lighter than the wood.
Walnut is dense and consistent: settings are repeatable from board to board, which is comfortable for small-batch production.
Cutting needs more energy than beech. On a diode the reasonable thickness runs out quickly; a CO2 is far more comfortable.
Risks and finishing
Mind walnut dust, which is irritant and allergenic for some people: extract and vacuum rather than blowing it around.
This is the wood where finishing makes all the difference: hard wax oil brings out the grain and engraving depth dramatically. Filling the engraved recesses with light paint is also a very elegant option on walnut.
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.