I work for a PCB manufacturer. All scrap has to be accounted for, and is
then sent for recycling (copper is costly). I've managed, over the last
couple of years, to get hold of some pieces of scrap, but these are few
and far between.

For cleaning boards, we use a sulfuric acid and pumice scrub. That last
part should be doable at home (I certainly won't be messing with reagent
grade sulfuric at home!). Maybe using previously mentioned lemon juice?

"Only two things are infinite, the Universe and human stupidity, and I'm
not sure about the former."
Albert Einstein

On Sat, 7 May 2005 13:03:33 -0400, (Padraigh
ProAmerica) wrote:

I work for a PCB manufacturer. All scrap has to be accounted for, and is
then sent for recycling (copper is costly). I've managed, over the last
couple of years, to get hold of some pieces of scrap, but these are few
and far between.

For cleaning boards, we use a sulfuric acid and pumice scrub. That last
part should be doable at home (I certainly won't be messing with reagent
grade sulfuric at home!). Maybe using previously mentioned lemon juice?

Basic white vinegar from the grocery store is a reasonably safe acid
to work with. Cheap to experiment with different concentrations, and
probably stronger than the lemon juice, certainly less expensive.

Happy trails,
Gary (net.yogi.bear)
--
At the 51st percentile of ursine intelligence

Gary D. Schwartz, Needham, MA, USA
Please reply to: garyDOTschwartzATpoboxDOTcom

Gary S. (Idontwantspam@net) writes:
On Sat, 7 May 2005 13:03:33 -0400, (Padraigh
ProAmerica) wrote:

I work for a PCB manufacturer. All scrap has to be accounted for, and is
then sent for recycling (copper is costly). I've managed, over the last
couple of years, to get hold of some pieces of scrap, but these are few
and far between.

For cleaning boards, we use a sulfuric acid and pumice scrub. That last
part should be doable at home (I certainly won't be messing with reagent
grade sulfuric at home!). Maybe using previously mentioned lemon juice?

Basic white vinegar from the grocery store is a reasonably safe acid
to work with. Cheap to experiment with different concentrations, and
probably stronger than the lemon juice, certainly less expensive.

I've never found anything on blank circuit board that couldn't come
off with just a good scrubbing, so obviously there is no need for
heavy chemicals. I seem to recall using soap at some point, which
worked, and I will try the vinegar.

The real issue is that no matter how shiny you get the boards, unless
you coat them with something they will tarnish with time.

Michael VE2BVW

On 7 May 2005 18:38:24 GMT, (Michael Black)
wrote:

Gary S. (Idontwantspam@net) writes:

Basic white vinegar from the grocery store is a reasonably safe acid
to work with. Cheap to experiment with different concentrations, and
probably stronger than the lemon juice, certainly less expensive.

I've never found anything on blank circuit board that couldn't come
off with just a good scrubbing, so obviously there is no need for
heavy chemicals. I seem to recall using soap at some point, which
worked, and I will try the vinegar.

The real issue is that no matter how shiny you get the boards, unless
you coat them with something they will tarnish with time.

Michael VE2BVW

True for most metals. Flux does a good job of removing the inevitable
little bit of tarnish/oxidation.

I did not mention earlier that it is very important to throughly rinse
off any acid, however mild, that you use.

There are ways to plate the copper with other metals less likely to
tarnish or oxidize, such as silver, or even gold in critical
applications.

Happy trails,
Gary (net.yogi.bear)
--
At the 51st percentile of ursine intelligence

Gary D. Schwartz, Needham, MA, USA
Please reply to: garyDOTschwartzATpoboxDOTcom