Random engraved pixels around edges of engraving

[ednisley]

@Chris89

Any advice on what is causing this or how to fix it?

This may be discouraging, but I haven’t seen anything to the contrary since pulling it together:

Where Those Random Dots in Engravings Come From

It seems everybody engraving acrylic with a CO₂ laser has seen random speckles appearing in places where the design shows a blank. Regardless of the suggested remedy in the many threads on this topic, nothing stops the dots. It turns out the problem lies inside the high-voltage laser power supply, which occasionally fires the tube at random, even though the controller has disabled the supply’s output. Although I’ve measured only two power supplies, other folks report random dots regardless of t…

The comments cover many of the first thoughts you may have, so they’re worth plowing through.

There’s a link to the background info on my blog:

CO₂ Laser Cutter: Random Dots On Engravings

Bottom line: it’s how cheap HV laser power supplies work.