How do you find laser settings with a material test grid?
Stop copying someone else’s numbers off a forum. A laser material test grid sweeps speed against power on a scrap of your real stock, so you read your settings straight off the sheet. Most laser software has one built in. It’s free.
Applies to
- Process
- CO₂, diode & fiber lasers
- When
- Any new material, new supplier, or new machine
- Test stock
- An offcut of the real material (3 mm birch ply for practice)
- Software
- xTool Creative Space material test array, LightBurn Material Test
Why it matters
Settings depend on the machine, the diode or tube, focus, and the exact sheet. Make or Break Shop adds humidity and altitude to that list. Numbers from someone else’s laser rarely transfer.
Even the presets built into your software are a reference, not an answer. xTool’s EasySet library hands you 20% power at 250 speed for 3 mm basswood ply, with a photo of their test card. Nice start. You still want to see the burn on your sheet, in your light.
A grid shows cut-through, char and engrave depth side by side. You pick the cleanest result instead of burning through material one guess at a time.
What good looks like
- A labelled grid on the real material, run on your machine at your focus
- Fast cells ran first, and you stopped once slower cells stopped telling you anything new
- You can point to the exact cell that cuts clean or engraves the way you want
- The winning settings are saved, so you don’t re-test next time
How to apply it
- Draw a square or circle and set its operation first: score, engrave or cut. The test array copies it.
- Open the material test (xTool Creative Space: Applications → Material test array; LightBurn: Laser Tools → Material Test).
- Set min and max power, min and max speed, the grid size (5×5 up to 10×10) and the spacing to fit your offcut.
- Keep focus, air assist and passes fixed so only speed and power vary.
- Run the fastest cells first. Slower speeds are where flare-ups start.
- Read the cleanest cell for your goal and save it as a named material setting.
Test it on your setup
- Cut test: if the fast row already cuts through at every power (say 16 mm/s), stop there. Slower rows just char the sheet.
- Multi-pass cuts: test one speed band at a time, and lower the focus between passes if your software offers it.
- Engrave test: add a logo or text next to the squares. A square hides edge and detail problems a logo shows.
- Inspect front and back, then repeat the chosen cell on a second coupon before the real job.
Exceptions & tradeoffs
Set the material to ‘user-defined’ when you run a test file. Make or Break Shop found a selected preset material can override the settings in the file.
A grid finds speed and power. Photos need their own tests for dithering mode and lines per cm — a square won’t tell you how a face will look.
Common mistakes
- Running the slow, high-power cells firstStart fast and work down only if you need to
- Building the array on an object set to score when you wanted engraveSet the operation before you generate the test
- Trusting the preset photo instead of your own sheetUse the preset as a start; check the burn on your stock
Frequently asked questions
- What is a laser material test grid?A grid of small squares, each burned at a different speed and power. You run it on a scrap of your real material and pick the cell that looks best.
- What speed and power range should a test grid cover?Wide on the first run, then narrower. LightBurn’s default sweeps 100–1,000 mm/s and 10–100% power; tighten it once you see which cells are useless.
- What material should I use for laser test cuts?The real material, from the same sheet if you can. For general practice, 3 mm birch plywood works well on both diode and CO₂ lasers.
- Should I run a laser cut test fast or slow first?Fast first. Slower speeds put more heat into the sheet, and that’s where flare-ups happen. Stop once a row cuts clean through.
Built-in material presets as a starting point, and why you still test on your own sheet — How to Find the Best Laser Settings ↗ at 01:00.
Building a material test array: operation first, min/max power and speed, grid size and spacing — How to Find the Best Laser Settings ↗ at 04:47.
Running tests fast-to-slow, stopping a cut test once it cuts through, and multi-pass focus stepping — How to Find the Best Laser Settings ↗ at 08:55.
A repeatable speed/power testing workflow per material — HOW TO FIND THE PERFECT LASER SETTINGS FOR YOUR MATERIAL ↗.
LightBurn’s default material test range (100–1,000 mm/s, 10–100% power) — Your Laser Settings Are a Hot Mess! Here's the Quick Fix! ↗ at 02:45.
Built from Make or Break Shop’s settings video. The fast-to-slow order, the stop-when-it-cuts-through call, the user-defined material tip and the 3 mm birch ply pick are his. His full test files are a paid xTool Creative Space download; everything on this page works with the free tools already in your software.