Homebrew PCBs

On Thu, Dec 30, 2010 at 2:22 PM, Chiphead <chiphead@...> wrote:
>
> > GrayDeal;
>
> Thank you for helping to rephrase the question.
>
> In addition to being easier to apply than paint, there are some comments
> from those doing it that you need multiple coats, and the paint isn't always
> a "solid" enough of a covering, even after multiple coats. Some feel that
> auto primer works better, as it tends to "etch into" the copper and adhere
> better.
>

I might make a suggestion here.  I was looking around at
higher-powered semiconductor lasers (deep blue/violet) and they
actually are making them in 1000mW (1W) intensities!  I've used 350mW
focused 650nm red lasers and they are sufficient to slowly melt/burn
black plastic.  With triple the power and being aimed at loose black
toner it might work.  Maybe.  My biggest concern would be that it
wouldn't stick to the copper and leave you a nice "skeleton" of fused
toner that would fall off.  I did some more digging and found an IR
laser at 2000mW (2W) for only around $248!
http://www.armlaser.com/2000mw-laser-module-2w-laser-module-p-11.html
 The site has a ton on different wavelengths and powers, and there are
a lot of sites around that sell similar stuff; it's just a matter of
finding some place that will sell to you.  The FDA has put limitations
on imports of high-powered (Above 5mW-- weak!) laser pointers, so
beware.  I would be more inclined to try and exposed photo-sensitive
UV resist with lasers than burn or cure toner, personally.  I tried it
at one point (250 mW deep blue) and it did work, but my plotter had a
terrible time turning the beam on and off correctly since it had a
force-feedback switch to tell when it hit the "paper" which I tried to
take over for switching the laser on and off.  Not good.

Larry