I understand that basically solder paste will stay good if refrigerated for about 3 to 5 months. I have a syringe of solder paste that has been refrigerated for about 6 or 7 months. Is it trash now or can it be rejuvenated in any way? Say maybe if I empty the syringe into a tray and remix it or should I throw it away and start over?
You’ll find that paste doesn’t really go bad, it just goes tacky. This means that new paste will be very pliable and easy to squeegie. Old paste becomes really sticky and nearly impossible to deal with. There’s nothing that I know to rejuv the paste. My recommendation is to buy smaller cotainers and change them every 6 months. We like 250g jars because we can use them up every 2-3 months.