My son and I are going to assemble our Overnight Sensations' crossovers. I have an old soldering iron that runs on 220 V and requires my converter... so I was thinking of using a 110 V iron. Radio Shack has 30 W, 40 W, 60 W all around $10 (the 30 W also comes with a bit of solder, a tool, and scissors), as well as dual voltages (e.g. 20/40 W). I picked up the 30 W kit. Will that be good all around for those crossovers as well as, potentially, beefier ones (I may build an entire 7.1 set if this goes well!) or should I increase the wattage?
Also, is very old solder still okay? I don't see why not but I am ignorant in those matters.