After a bit of foolishness, I found myself with a 9 year old Delta Shower Faucet Valve body in my hands in two pieces. The cartridge housing was in one hand, and the brass cross was in the other. Three copper tubes were severed. Each copper tube approaching the valve had a union on it relatively close to the valve body so that it could be pulled through the access hole in the shower. The valve body has female threads.

I attempted to purchase an identical valve and found that Delta has changed their design to a much larger brass cross with male threads. Then, I went to a couple of hardware stores and looked at a lot of valves. They were all larger brass crosses, and most had male thread connections.

I have no desire to tear into the exterior wall to redo the tubing and connections required for a new valve.

Now, the real foolishness has started. I have milled out the broken copper tubes from the brass cross, and from the cartridge body, and purchased some new 3/8 copper tubes to reinstall in the body.

My question is how do I solder the copper tubes to the brass? I do not know if the brass cross is a copper/zinc, or a copper/aluminum. What type of solder (or braise) and flux would you recommend? Do you have any tips for attempting this procedure?

You shouldn't have any trouble putting this back together using 95/5 solder and a plumbing grade flux.