The material test array is the single most useful feature in the software, and most people don't run it until they've wasted a sheet of good material.
What it does
Engraves a grid where one axis varies power and the other varies speed, so a single tile shows you dozens of combinations on the material you actually own.
How to run it well
- Use the real material — same supplier, same thickness, same batch as the job. Plywood from two suppliers behaves differently.
- Sensible ranges: for engraving, 10–100% power against a wide speed spread. For cutting, high power and a narrow slow speed band, and mark which cells went all the way through.
- Label the axes on the tile itself so it still means something in six months.
- Write the winning numbers on the back in pencil.
- Drill a corner hole and put the tile on a keyring, one ring per material.
Read it properly
You're not looking for the darkest cell. You're looking for the cell with the cleanest edge definition at an acceptable darkness — over-burnt cells look bold at arm's length and mushy up close.
Re-run the array whenever you change material supplier, clean or replace the lens, or notice output drifting.
LaserPecker publish their own documentation on this topic — worth reading alongside these community notes.
Official article