Thanks for the report.

I am not surprised by this first test. The foil is very thin. I should have mentioned how hard it is to transfer without wrinkling, etc.

A couple of ideas, maybe a good, maybe not.

Get unplated FR4, stick the (probably thicker) copper foil to it, then cut on that. I don’t know how hard it would be to weed, though.

Cut a negative mask, weed it, the spray on something for resist (not sure what, but it seems doable), then etch.

 

Excellent ideas. What would happen if you throw a laser engraver into the equation? I wonder if it would cut the copper cleanly or at all, if not maybe a more powerful engraver? Then you would need to deal with the fumes etc.

 

Excellent ideas. What would happen if you throw a laser engraver into the equation? I wonder if it would cut the copper cleanly or at all, if not maybe a more powerful engraver? Then you would need to deal with the fumes etc.

I think a laser engraver would be much better suited to this; actually I was thinking this while watching the Cricut's blade clumsily smear my copper traces around. I thought, using a laser on a copper clad board would be tricky; to etch just the copper without burning through the board. But for this process it's just fine to burn through whatever is behind the board. But, being distracted as I was by failure playing out in that moment, I didn't google "laser engraving copper PCB" until just now when I was reminded by your post to do so. That is when I found the evidence that I had been looking for. The evidence that I am not the first one to think of this. As usual, beaten to it by years. Even the Capton/copper sandwich FPC. Apparently, totally doable with a CNC Laser.

EDIT: He is spray painting, laser-etching the paint, then chemically etching the exposed copper. I'm talking about burning straight through the copper with the laser. So I maintain some element of originality. Just want to clarify that.