Spray Paint / Laser Cutter PCB Resist

The homebrew PCB group has come up with an interesting method of very VERY quickly making PCB's on a laser cutter.
https://groups.yahoo.com/neo/groups/Homebrew_PCBs/conversations/topics/35041

1. Clean PCB blank and spray with black / dark paint.
    
2. Laser at low power / high speed to burn away paint around traces (isolation) or raster for removal of larger areas. The Laser burns off the black paint, but is reflected by the copper. This has been tested with a CO2 laser and works very well. Fumes are, of course, a serious issue. Don't try this if your Laser cutter exhaust is just filtered and released into the room.
    
3. Etch. The remaining paint protects the copper from the etchant, but where the paint has been burned away, the copper is exposed and removed by the etchant. Tested, works nicely.
    
4. Leave the paint in place over the traces (as soldermask) and Laser again to burn away paint from solder pads. Tested, works nicely. In fact... spray the etched board again with green paint (or whatever color) and laser that clear off the pads for a really nice soldermask. Don't tell me the paint can't manage the solder heat because there are very high temp paints.
    
5. New idea: If you etched out a hole in the center of each through hole pad, by burning away the paint where you would normally drill, and if you have a high enough power laser / take it slow, you might be able to laser cut your holes through the FR4. (!!) This could even be extended to cutting out the PCB from the blank, including complex shapes.

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