ArtMetal

I like phos copper rod. The rod melts pretty easy and no flux. There are few different levels with more silver and more expensive. But the Harris "O" is the favaroite among many. http://www.harrisproductsgroup.com/consumables/alloys.asp?id=31

You can call your local welding supplier and have them order you a pound. If you use just a little bit it will blend in with the copper. It has a copper color to it after you weld and pickle. If you sand off the excessive it will leave a nickle color. It will accept all patinas and you can not see the weld. If you want a contrast then just braze using standard brazing rod and flux. Any powdered brazing flux will work. You just need to make sure to remove any flux so that it will not salt around the weld where flux was left. What you may want to keep in mind is that if you have to do any more annealing than you cannot use solder and phos copper will also start to flow. If I run into that type of situation I braze. warren