I use rosin core solder electrical (lead-tin alloy) solder which holds ok. The problem comes when both connections are not cleaned properly so the solder does not flow. If it beads up, it's not a good conection.. in fact, it's not a connection at all. It has to flow into the joint for the solder joint to be secure.

Silver solder requires more heat than lead-tin soldering does. The differences in strength are obvious, but it is not necessary in most applications to have a joint that is that secure that you need silver to make it so. Most lead-tin soldering will not get the parts heated up to glowing red where silver solder will.

CGr.