Silver solder will work fine but not on alum. You can use Brass or steel with no prob. You do need to use a good heat source, not a propane torch like you get at wal-mart, but oxy acetalyne or map. BTW the melt point for most Silver solder is 1100, there may be some older stuff around that will melt around 850 but it has cadmium in it and puts off some bad fumes. Most of the time you will find the cad free stuff.