If you are making PCBs or jewellery, you'll know about using resist, paint or other form of barrier to prevent the copper being etched by acid/electro etch.
I've always wanted a good way to remove resist without having to use UV reactive film and all manner of others ways. Yes, you can mill the copper but I'm not that happy with the results, and that is also no good for jewellery etching where there is no substrate.
So I've been playing with the jewellery technique of painting the copper with Matt black spray paint and then once dry, removing the areas you want to etch using the JTechPhotonics laser on my X-Carve.
Ignoring the fact these tests were using Easel, where you cannot turn off the laser while its doing Z up/down and rapids, it looks like the ablation will work well, maybe even better than milling.
I'll repaint these tomorrow and run the jobs again with a GCode export from Easel and change the Z movements to laser on offs and resend from Chillipepr.
Then they'll go in the salt water, low speed electro etch tank, takes a day or do, and see what happens. Once out of the tank, a quick wipe down with acetone will remove the paint. (Need to use an acid etch on PCB due to the break in conductivity once PCB tracks start to form).
Anyway, enough talk, here's an ablation piccie. Do bear in mind, if you try this that burning paint is really, really bad for you, so you need excellent air handling or proper respiration filtration.