This ng sure has been quiet lately.
I have an interest in some old Onan generators and so have signed up for a forum called "smokstak.com". There are many metal-related forums in it, the Onan part being only one of the many.
There is a blacksmithing and metalurgy sub forum and here it is:
Joining copper parts: THE BIG THING: This material makes joints that are almost the same color as the copper!!! I recently bought a Harris rod to use in joining copper parts. It is called "Phosphorus Copper with NO silver". The guy who told us about it called it a "welding rod" but indeed it for brazing, since you don't actually melt the parent (copper) metal. It comes in a few different shapes, but the one I bought has a rectangular cross section; 0.050" X
1/8". If you start with clean copper, you don't need any flux. Once you get a puddle going, you can easily use the heat source to suck the material along the joint.
A tube about 18" long with about 20 rods cost me about $22.
A nice soft oxy acetylene flame would probably be best, but I made a couple of samples using a hardware store Mapp gas torch and it worked quite well. I had to learn to NOT overheat the parts, ie: keep things down to a low red heat for best results.
Pete Stanaitis
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