Laser cutre Cooper?

Can you cut the copper, with a laser, to make electronic cards, pbc? What power do I need?

I don't know, but it looks like something that you can't do with a cheap-small laser. You can melt solder with a 25-30W soldering iron, but it won't melt copper. But, the power of a laser is more concentrated/focused...

Googling a bit, I found a lot of references to removing etch resist/paint with a laser before regular chemical etching.

I found this which says they did it with a 30W "fiber laser", whatever that is.

[u]This site[/u] says they were able to make steel traces with a 40W laser, but they failed with copper.

It looks like [u]this machine[/u] can do it, but they don't give the laser power. It's a big machine (500 LBS), the power supply is 1.2KW, and you have to fill-out a form to get the price.... Not for hobbyists.

Can you cut the copper, with a laser, to make electronic cards, pbc?

Basically no. If the beam is strong enough to vaporise copper it will piss through the substrate
You might be able to remove copper with RF spluttering, I used to do this with thin film substrates of glass nichrome and gold, but I have not seen a commercial machine to do this.

You will notice that on that link to the PCB laser the substrates were all much heftier stuff than you normally use for PCBs

A wide range of substrates can be processed included copper-clad FR4, aluminum-coated PET films, ceramics, Rogers TMM®, RT/duroid®, RO4000® and PTFE based materials up to 9" x 12" in size.