Laser diode to remove copper layer from PCB

An ordinary laser diode won't cut it (literally). You need something like a Q-switched laser, pulsed at 10's of kHz. The peak power has to be extremely high to ablate copper (>2500°C), and some nasty fumes come off the epoxy substrate, which have to be exhausted.

Even a 40W \$CO_2\$ CW laser won't cut thin metal foil- it just bounces off.

Here's a commercial unit (costs as much as a really nice automobile).

If you really want to fool around with this sort of thing, you can find suitable lasers on the surplus market, but it's not going to be a matter of attaching a little diode to an engraver head.

Class 4 lasers are not toys!

I used a 808nm 0.5W laser diode and it can remove paint from over the copper layer.

I have explained it in the posts of my blog, from buying to the current results. The URL is:

http://gabuleu.blogspot.fr