I’m trying to laser-etch transparent extruded acrylic using my NEJE A40620 diode laser (blue laser, 450 nm). To make the surface absorb the laser, I painted it with red automotive spray paint. My settings were:
Power: 8%
Speed: 6000 mm/min
Passes: 2 (front and back sides)
The laser successfully removed the red paint, but it did not etch or mark the acrylic surface underneath on either side.
I understand that clear acrylic doesn’t absorb blue light well, but I was hoping the paint would help. After reading more, it seems red might reflect too much of the blue laser light.
My questions:
Should I use a different coating color, like black, to help with absorption?
Has anyone had success etching clear acrylic with a diode laser using a black film or paint?
Would switching to cast acrylic instead of extruded help improve the results?
Any recommended power/speed/pass settings for this laser on coated clear acrylic?
Appreciate any tips or examples from those who’ve made it work!
I haven’t tried to etch clear acrylic with a blue laser.
That said, a couple of experiments you might try:
do a power test grid (like the one LightBurn makes, 8% power seems pretty low power for a diode)
Use a thin coating of titanium dioxide paint (bright white paint) with a bit more power. If this works, you’ll end up with black engraving of the material. It will be tough to apply the paint evenly.
I have seen videos like this before and tried it my self. I was not able to achieve the same results as they were. I might could have gotten it with a LOT more trial and error. But acrylic isn’t cheap so I just use a Diamon Drag Bit on the LR4 and get what I need. Not as fast as a laser would be, but it works and its quite lol
That seems like a software issue. You could just convert it to svg using inkscape (easier said than done, but possible with most images you’d want to etch).
Since he is wanting to use a bitmap image I assume he wants more than just black and white. He is wanting the gray tones as well, which the laser can do. The drag bit not so much. I could be completely wrong though.
