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

I’d say ‘No’, the main reasons being the Cermark is very expensive, doesn’t work all that well on copper and doesn’t appear to work well as an etch resist.

As Cornelis said, plain black paint works well enough.  Burn off where you want to etch and the remaining paint works as a resist.

I’ve been meaning to get around to lasering PCBs, I did have a quick play with paint on other metals to see if I could mark them with paint. 

Defacing the Commonwealths currency: https://dl.dropboxusercontent.com/u/31090134/Laser/2016-02-04%2008.50.28.jpg which worked reasonably well.  Those coins are a copper/nickel mix.  75% copper?

Images on a steel dog tag: https://dl.dropboxusercontent.com/u/31090134/Laser/2016-02-04%2008.53.59.jpg, https://dl.dropboxusercontent.com/u/31090134/Laser/2016-02-04%2008.51.42.jpg.

Power levels are a bit finicky, that second dog tag photo is the back of the tag and shows things got a bit too hot.

You can set the power low to burn the paint off, or high to leave a mark (positive vs negative images).

Cermark is a bit finicky too, video here: https://www.youtube.com/watch?v=b_06laAjMPc where he tests at different speeds & power, and compares it to cheaper molybdenum disulphide (lubricant).  Someone in the comments mentions mixing plaster of Paris with rubbing alcohol.  I double any would work as a resist for copper etching though.

Tony