Every laser, every lens and every sheet of material is a little different. The settings someone posts online for “3 mm birch ply” might be close for your machine, or might set it on fire. The only reliable way to get clean cuts and even engraving is to test.
What a test card is
A test card is a grid of small squares. Each row uses a different power and each column a different speed, so one quick job shows you the whole range. You pick the square that looks best, and those are your settings.
How to make one
- Choose a power range (for example 20% to 100%) and a speed range that suits your machine.
- Lay out a grid, typically five by five, with each square on its own colour layer.
- In your laser software, give each colour its own power and speed from your list.
- Run the card on an offcut of the exact material you will use.
Doing that by hand in LightBurn takes a while. Laser Test Card builds the grid for you, gives every square its own colour, and saves a colour key listing the power and speed for each one. It also warns you if your grid needs more colour layers than LightBurn allows.
Reading the results
- Engraving: look for an even, consistent tone without heavy charring at the edges.
- Cutting: find the fastest speed that cuts cleanly through in one pass. Faster cuts usually mean less scorching.
- Leather: check the back as well as the front, and smell it: a strong burnt smell usually means too much power.
Always test on the same batch of material. Two sheets of “3 mm ply” from different suppliers can need quite different settings.
Keep a settings book
The most useful habit you can build is writing down what worked: the material, its thickness, your machine, the power, speed and number of passes, and a note or two. Next time you pick up that material, you go straight to the right settings. Laser Test Card keeps that book for you, searchable by material or machine, and you can export it as a spreadsheet.