Homebrew PCBs

2009/1/20 sjlanejan760 <sjlane60@...>:
>Laser engravers are
> Raster devices so to burn the "resist" off a complete board would mean
> scanning the entire board too remove the "resist"

Not all of them - mine's vector, and only kicks down to raster when
it's doing bitmap stuff.

> (I offset the projected cost by making
> engraved name tags when I'm not indulging in the hobby)

Yeah - anodised aluminium marks superbly - I use it for product tags /
serial numbers. It's also handy for burning serial numbers onto the
edges of PCBs...

> On the subject of using CO2 Lasers to "cut" copper as I understand
> it the actual mirrors in a CO2 Laser are coated polished copper as the
> radiation is in the infrared range so anything strong enough to cut
> copper would also burn the mirrors up in the process.

Sort of - but the beam when it goes through the steering optics is
rather wider (and lower power density)  than it is when it finally
hits the target (or, at least, it is in my setup, I don't know about
the gantry systems).

>I believe that
> to cut copper you need to use a YAG Laser and a air/gas jet to blow
> the cut material out of the cut.

That seems to be what the laser-drill PCB shops use.

Steve