Laser Test Paper

A pack of Black Laser Engraving Testing Paper arrived and I put a few snippets to the test:

That’s the standard backlash test pattern shrunken down to a little over an inch wide, with the laser power reduced to the bare minimum. Despite that, the numerous holes show where the pattern concentrates enough energy to vaporize the paper.

The “paper” seems to be laminated between two black plastic sheets that smell terrible when engraved, so they’re probably some form of acrylic. The Amazon product description is, despite all the verbiage- remarkably uncommunicative of the actual materials involved.

The circular pattern is 10 mm diameter on the outside:

Those should be circles around the perimeter, but their distortion shows what happens when you try to move a hulking CO₂ laser head around a 1.5 mm diameter circle at 400 mm/s. Of course, the actual speed is nowhere near that fast along such tiny vectors.

The traces are about 0.2 mm wide, with obvious scorches where the beam starts and stops, which agrees reasonably well with previous measurements.

All in all, both the paper and the laser pattern look better than I expected, particularly as the results indicate the machine has no measurable backlash at all.