Smitty Two said:
Good considerations, and I'm hardly in a position to disagree with your
experience. My thinking is that if it's water soluble flux, use water.
If not, the water just reduces drying time, reduces cleaning
effectiveness, and helps to exacerbate the spreading of flux residue
over an increasingly larger area of the board.
Of course, for most repair work, that's not an issue. Perfect cosmetic
cleanliness is demanded of me by my commercial customers, so a little
irregularly shaped stain of flux residue, however slight, just won't
fly. Your average consumer isn't going to notice or expect that.
It's good to remember that rosin flux is non-corrosive and
non-conductive and there's no real need (other than cosmetic) to clean
it up at all, while water soluble flux is definitely corrosive and
should be pretty thoroughly removed soon after use.
Rosin-based flux comes in several levels of activity. Type R (rosin) flux
contains rosin only, with no cleaning agents. RMA flux (rosin-mildly activated)
contains a nominal amount of cleaning agents, and RA (rosin-activated) flux
contains a fair amount of cleaning agents. The cleaning agents act on the
metals being soldered to remove surface contaminants and float them away so the
metals are adequately wetted by the solder.
The RMA and RA fluxes are corrosive if insufficient heat is applied to the
fluxed area during solder to neutralize the cleaning agents, and over time will
definitely cause problems if not properly cleaned after soldering.
Water soluble fluxes are more active than any of the rosin-based fluxes.
Organic flux is more active than RA flux and inorganic flux is the most active.
Obviously, all fluxes need to be cleaned after soldering to avoid any
possibility of contamination or corrosion. Mil-spec soldering requires that all
flux residue be removed after soldering is complete.
--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate characters in the
address)
Life is like a roll of toilet paper; the closer to the end, the faster it goes.