brass.

I had tried both methods with only very limited success and lots of cold soldered joins. The only time I succeeded in making a strong welded join was to use silver solder that needs a hot acetylene-air torch with borax as flux.

I did this recently for a wooden stage coach model. I used an electronics soldering pencil with a 45w element, a chisel tip, & 63/37 solder. The trick is to make sure the brass is as clean as possible. I use sandpaper to clean it, then tin it. Hold the iron on the brass & add a little solder to the iron where it contacts the wire. This aids in heat transfer. Then hold the solder where you wish to join the two pieces. You should never put the iron tip at the joint to be soldered directly (see crappy depiction below). You might also need heat sinks. These shunt heat away from areas you might have already soldered, & also give you something to hold on to.

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