I have a hunch that when the above says "silver solder" they really mean silver bearing solder such as StayBrite. True silver solder requires a great deal more heat and necessitates a torch, not iron. Silver bearing solder does require slightly more heat than regular solder but does use an acid flux so you need to clean the joint well after soldering as well as before else you will soon have a lot of corrosion. For most RC use, regular electical solder with rosin flux will do fine although it is sometimes easier to make good solder joint on music wire using an acid flux, again scrubbing well after as well as befor soldering.