"Jim Land" wrote in message
. 3.44...
"Arfa Daily" wrote in
:


Sorry, don't know how that got switched on. It's set for " plain text
" again now, as it usually always is ...

So, aside from the formatting gripes, any comments on what I was
really asking :- ) ? It's a serious question that I'm interested in
answers to. There must be some posters who better understand the
chemistry of soldering and flux than I do.

It's all a matter of words.

Here's the deal. For decades there have been two classes of flux used
for soldering.

1. Acid. This contains strong chemicals to aggressively clean the metals
and is used only for plumbing and similar soldering. It must be cleaned
from the joint after soldering, or corrosion will occur. It has NEVER
been used for electronic work because of this corrosion.

2. Rosin. This is the only flux used for electronic work. It contains
such mild chemicals that it doesn't need to be cleaned after soldering.

Your worry is about "acidity", which is probably nothing to worry about,
as long as you stick to rosin flux and never, ever, use "acid flux."

OK, thanks for the answers. I don't have any " worries " about fluxes. It
was just curiosity as I have never seen anyone making the distinction before
with regard to electronic soldering. I have been soldering virtually every
day of my life for 40 odd years, and have always used 'standard' rosin flux
cored solder, which was the only variety I had ever seen offered for normal
electronic work. I had always understood the material rosin, to be mildly
acidic, at least in its activated form, and that this was the basis of its
deoxidising properties. This was the only reason that I was interested in
comments about " never use acid flux " ( I was not the OP having soldering
problems, incidentally ).

So it would seem that the point is academic anyway, as such fluxes are not
offered for electronic work, and anyone dumb enough to try to use plumber's
flux would deserve all they got ...

Just as a matter of interest, I always remove rosin flux residues from
boards, using a proprietory flux remover from Electrolube. IMHO, post
soldering residues left on boards make the job look scrappy and
unprofessional. A couple of years back, I took over the repair of some
commercial boards from another company, who never cleaned up their work.
Interestingly, when I now see boards in for repair, that they did a couple
of years back, the joints and print area around where they've left flux
residues, often look slightly corroded. The air around them in their normal
working environment, is likely to be slightly moist, and the components that
have been replaced, run hot in normal use, so I wonder if this is slightly
reactivating the flux residues ?

Arfa