What is the shelf life of brazing paste?
Brazing paste that is in its original unopened container is warranted for 90 days. Similarly to the flux, this warranty does not mean that after the 90 days, the paste will not function. Functionality can only be determined by melting the paste to see if flows or not. If the alloy flows then it is still functional, conversely if the alloy balls up then it is not functional.