Freezing Solder paste and Flux ?

[Fraser]

I am starting out on a voyage of discovery having just purchased my first Hot Air Station for SMD reflow and repair work.

Having read about the various solder pastes and fluxes I have started with some of the cheaper products that are available to see how well (or not) they perform before considering some of the much more expensive products.

The solder paste is a 50g tub of 'Mechanic' MCN300 Sn63/Pb37. I bought two types of flux for rework, an alcohol based 'no clean' liquid and a thicker Chinese RMA-223 that claims to be Amtech and definitely is not !

I understand that these chemicals tend to deteriorate with time and temperature such that they can become unusable after a few months. Refrigeration is required to prolong their useful life. I further understand that the solder paste tends to separate with the lead beads ending up at the bottom and flux at the top. Again refrigeration apparently slows the process down to extend useful life.

I am unlikely to use all of the material that I have bought and it may sit around for weeks awaiting the next requirement for its use. Has anyone had any experience of the general useful life of these materials in the hobbyist domain as opposed to the strict industrial environment that requires guaranteed quality ?

I am also wondering if anyone has tried freezing solder paste to extend it's operational life ?  

[mikeselectricstuff]

If refrigerated it usually lasts a lot longer than its rated shelf life - can be a few years.
Make sure it's sealed as evaporaiton and moisture ingress are the main problems.

[metalphreak]

If it dries out, you can always mix in some more flux paste to make it usable again. This is obviously not the best practice for a production environment, but for hobby use and such its fine.