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make.co
FEELING THE FLUX
I always thought a separate supply of flux was just
for plumbers, since electronic solder has its own
flux in a hollow core. What I failed to realize (until
a friend made it clear to me) is that if you take too
long to make a joint, the flux in solder can boil off,
with nasty consequences.
See for yourself. Try melting a quarter-inch
blob of flux-cored solder on the spade-shaped tip
of a medium-power iron, and let it sit there. The
fumes you see are the flux going up in smoke.
Wait 30 seconds for the fumes to stop completely,
and then apply the solder to a thick piece of wire.
Heat it for as long as you like; the ...