Laser Settings Library

A common starting point for a 20W diode laser cutting 3mm (⅛") Baltic birch plywood is 600–800 mm/min at 100% power, 2 passes, with air assist on. A 10W diode typically needs 3 passes at 400–600 mm/min. Always run a test grid on scrap first — material density and moisture content vary batch to batch.

Diode lasers (808–940nm wavelength) work well on dark or absorptive materials — wood, leather, anodized aluminium, dark acrylic — but struggle with clear acrylic and glass. CO₂ lasers (10,600nm) cut clear acrylic, fabric, and thick wood efficiently because that wavelength is absorbed by most organic materials. Fiber lasers (1,064nm) mark bare metal — stainless steel, brass, copper, titanium — without any coating. The same wattage in different laser types is not directly comparable: a 40W CO₂ cuts far faster than a 40W diode.

254–300 DPI is the standard sweet spot for photo engraving on wood. Higher DPI (400–500) can improve fine detail but risks over-burning in dense areas. The optimal DPI also depends on your material: coarser grain woods like pine tolerate lower DPI, while maple and cherry hold detail better at 300+ DPI. Use a stucki or jarvis dithering pattern for smooth tonal transitions.

Air assist is a stream of compressed air directed at the laser's focal point during cutting. It clears smoke and debris from the cut path, reduces charring, improves cut quality, and — critically — reduces the risk of material catching fire. Use air assist whenever cutting wood, acrylic, leather, or any organic material. For engraving at low power, it can be turned off to allow a darker mark.

The most common causes are: (1) focus is off — the focal point is not at the top surface of the material; (2) not enough passes — increase from 1 to 2 or 3 passes; (3) power is too low or speed is too high — reduce speed by 20% or increase power; (4) material is thicker than expected; (5) lens is dirty — clean the lens with IPA and a lens wipe. Always run a focus test and a power/speed grid on scrap before your final cut.

For a 10W diode laser engraving vegetable-tanned leather, a typical starting point is 2000–3000 mm/min at 40–60% power, single pass, 254 DPI, air assist off (air can lighten the mark). Chrome-tanned and synthetic leather behave differently and may require lower power to avoid melting. For a 40W CO₂ laser, start at 300–400 mm/min, 15–25% power. Always test on a scrap piece first.

LightBurn is software that runs on compatible machines — most diode lasers (xTool, Sculpfun, Atomstack, Ortur, Commarker) and CO₂ lasers (OMTech, Monport, Boss, Thunder Laser) support it natively. Glowforge uses its own cloud software and does not support LightBurn. The settings themselves (speed in mm/min, power as %) are machine-specific and do not transfer directly between different machines even with the same wattage.

Slate engraves well on diode, CO₂, and fiber lasers. For a 10W diode: 1500–2000 mm/min at 80–100% power, 254 DPI, single pass, no air assist. For a 40W CO₂: 250–350 mm/min at 20–30% power. The laser ablates the dark surface coating to reveal the lighter grey stone underneath — higher power gives a higher contrast result. Cool the slate with a damp cloth before engraving to reduce thermal cracking on polished pieces.