Was gathering all my solder up to see what I had and found one roll of 63/37 no clean core with a 3 year shelf life. This was a bit of a surprise as I never thought of solder having an expiration date. Heck I know I have solder that is more than 20 years old that I use all the time without issues. This particular roll is 5 years old and 2 years past it's expiration date. I'm not going to worry about it a whole lot and will be using it. It's the only roll of 0.015 I have, at the rate I use solder that small this roll will be around long after I'm dead and gone.

Wondering if anyone has ran into any issues with old solder. Can't imagine the tin/lead going bad, must be the flux that has a shelf life.

 

The only concern I would have, is the tarnish. I, too have solder that is from the '60's with no notable diminish of quality. I just pull it through a terrycloth rag saturated with denatured alcohol, and use it anyway.

 

I have experienced joint failures/issued due to expired solder. It was a few years passed its date and would not wet properly. Think it was 63/37 rosin flux core

Its the flux thats got the shelf life. I've had users ruin full 5 gallon buckets of flux by simply forgetting to screw the top back on. The solvents just go "bye-bye"

 

Yep, it's the flux. But the point of the shelf life is that it will still be within performance specs for production work at least until the end of the shelf life, provided the storage conditions are satisfied. The thinner solders generally have shorter shelf lives, but only because the type of soldering they are intended for are more sensitive to flux degradation.

I use a rosin paste flux (thin paste, almost a fluid). It's also old (pushing 20 years) along with my 0.008" solder that I bought from a surplus house well over a decade ago. But I'm still able to do 0.5mm pitch parts with no problem. Don't know if that will continue indefinitely, but I suspect that if I get new paste flux I will be able to tolerate the degraded core flux as long as it doesn't poison the joint, which I don't think it would.