Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

Witj my CO2 laser I had to play a bit with the power settings. Too low and the paint did not 'vaporize' properly. Too much and you actually damage the copper (in rastermode a pulse actually can have a lot of power!)

Just right leaves a dull ash on the board that i simply wiped off with a water sponge before etching and then used a sponge to wipe etchant over the board too.

I don't have fotos now, but I got very crisp traces. I am pretty sure i got 12mil lines and spacing too.

I just use normal black spray paint. Not high temp stuff.
I drill the holes first on my cnc mill. With say 4 alignment holes. Then spray both sides.
Then I 'drill' the 4 alignment holes in a mdf wood base with my laser and insert locating pins in them.
Pcb goes over pins.
Laser TOP side design onto painted board
Flip board onto pins again
Laser Bottom
Check hole aligment with tracea etc....
Etch...

The only annoyance in Pcb making for mw now is the lack of thoughole plating!

And the fact that I have to use 2 machines
Hench why I just bought one of these off banggood to which I'll stick a pcb drill on a diy z axis so I can laser and drill without moving pcb
Not bad for $215