2. Solder paste doesn't keep (seems to have about the same time constant
as Horowitz & Hill's wet fish)

Solder paste must be kept refrigerated to maximize its shelf life. (read the
manufacturer's storage and handling instructions CAREFULLY, both for proper
storage for product longevity and for safety reasons)

I sure hope "solder paste" is NOT the same thing as "soldering paste flux",
or else my shoe-polish-size can of "Kester Soldering Paste Flux" (with a
hole in the lid through which I occasionally poke a soldering pencil)
that's been sitting on my workbench for at least the last 25 years hasn't
heard about those storage and handling instructions!

--Myron.
--
Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge
PhD EE (retired). "Barbershop" tenor. CDL(PTXS). W0PBV. (785) 539-4448
NRA Life Member and Certified Instructor (Home Firearm Safety, Rifle, Pistol)