Homebrew PCBs

"Jeffrey Jenkins" <tesseract@...> writes:
> BTW - do you have to run the boards through more than once? Preheat
> them at all? Anything special? Pulsar's website is kind of sparse on
> the details on using the laminator and I know from experience that
> the devil is in the details when it comes to this stuff.

I normally run the board through a couple of times, at various angles.
Traces that run parallel to the rollers seem to get less well
transferred than those that aren't.  I also use different parts of the
rollers, if the board is small enough, although I have no proof that
that helps..  So far, I've yet to have a case where there was too much
heat applied (no smeared traces), although a couple of times I've had
traces not stick well enough (didn't wait for the TIA to heat up all
the way, was too impatient with the water bath).

The other trick is to include a thick trace surrounding your board(s),
which holds the paper down around the edges.  Otherwise, stress on the
paper hits the board's traces first.  If the boards are really small
(my smallest are often in the 0.3 x 0.5 inch range), I put more than
one on each "panel" so if one has a broken trace, I can just use
another one.

My etchant is warm FeCl, wiped on with a sponge (a Pulsar trick).
Very quick that way, but you have to use the green TRF.

I'm still trying to figure out the paper though.  I have two types, an
older white pack, and a newer blue pack.  At the moment, the white
gives better results, but I don't know why.  I've tried humidifying
the blue, but it just doesn't seem to take up as much toner out of the
printer as the white does.  Next time I'm going to try running it
through the printer twice (the first time, not printing anything) to
see if prepping the paper helps it take up more toner.