Oak is a hard, dense, high-contrast wood: engraving comes out deep brown, almost black. Its irregular grain and tannins, however, make it markedly less predictable than plywood.
Settings: what really matters
Oak alternates soft (spring) and hard (summer) zones within the same board. As a result, at constant settings engraving digs deeper into the soft zones. That is unavoidable — work with it rather than against it by orienting the artwork along the grain.
It needs more energy than plywood at the same thickness. A 10 W diode engraves oak very well but reaches its limit when cutting: past 4 mm, plan on a CO2 or many passes.
For fine engraving on a board or a solid object, two light passes give a more even result than one heavy pass, which exaggerates density differences.
Risks and finishing
Oak is rich in tannins: smoke stains the pale wood around the engraving for good. Paper masking tape is almost essential here on a visible piece.
Dense and dry, it can ignite on a slow cut. Check for embers before closing the machine.
For finishing, hard wax oil reveals the contrast beautifully. Careful: on oiled oak, later engraving becomes uneven — always engrave before finishing.
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.