In soldering copper pipes can lead-free, water-soluble flux be used with 50/50 tin/lead solder?
It will work but lead based solder is not allowed for water pipes, at least not drinking water. Heating systems, ok. But the 50/50 seems like an odd alloy. The higher lead content will mean a very high melting point. Usually 60/40. For electronics and pipe. Why not use the lead free solder? Don't like it for electronics but is fine for pipes. Edit: Actually for electronics it is usually 63/37 eutectic
It will work since the heat is what activates it for cleaning the pipe. Not sure why you are using 50/50 solder though since it isn't approved for drinking water lines. I would use lead-free or 95/5.
