On Fri, 29 Apr 2016, Ralph Mowery wrote:


Does the flux in solder really get old ?

I have some of the older 60/40 flux core that is over 20 years old and
never had any problems with it.

I once bought a roll of solder, maybe the price was great, and I thought
it wsa 60/40 or some slight variation, but it never worked. I remember
being puzzled at the time, but it's long enough ago that I don't know.
Maybe it was odd solder to begin with, but at the time I thought maybe it
was stale.

That said, other than that role, I've never had problems. I think I've
gone through two decent rolls over the decades (and small rolls) and other
than that one roll, I've never had problems.

I thought it was when the solder was soldered that problems arose. I
remember having problems desoldering old tube equipment, the flux gone or
something, only by adding some new solder did the old flow properly.


Michael


Just getting into the SMD soldering and the tubes of solder paste have
an expiration date on them of about a year and some want to be kept in
the refrigerator when not being used. Also bought some liquid flux and
it mentions an expiration date about a year or so later.

Just being a home user it may take me years to use the stuff. I know
lots of things have an expired or use by date on them,but that does not
really mean much. I think the government just requires a date on some
items.