- REFRIGERATION
Always keep your solder paste refrigerated when not in use. That way, you can keep in tip top shape as long as possible.
- USAGE
Take it out of the refrigerator 3-4 hours before you use it optimally speaking. Once you’re finished, put it back in. We’re obviously not manufacturers, so we don’t use the whole tube, and we have to compromise with that.
Use what you need to use. A bit more is better than a bit less.
- TIME FOR BEST USE
Ideally, you’d use the solder paste within a year, but if you can use other stuff to help you out, you can use solder paste up to 5 years(personal anecdotal experience) within any trouble.
- HOW TO GET THE BEST SOLDERING JOB POSSIBLE WITH FLUX
Flux, flux, flux! Flux is your best friend. The older solder paste you have, the more it helps. I’ve managed to save a lot of old solder paste just by using any kind of flux. Using it prevents oxidation and removes oxidation as well.
- SURFACE PREPARATION
Just cleaning with isopropanol is good.
- SOLDERING
I personally use a hotplate for soldering, but an oven with iron frying pan that has a lot of thermal mass is best for this kind of thing, as it mimics the initial style of heating in commercial soldering. If you have plates with time based temperature control, that would be best.
As for a natural gas oven, it is fine, but make sure to stop the heat completely when the SMD part is soldered(like an LED).