Had to help a neighbor fix a plumbing problem. A leak where the water main enters the outside wall of his house. Hey, there a drought going on and it was a weekend.
I’ve used lead free solder for years, but I sometimes have a problem making a good joint with it. I always make sure the joint is shiny bright clean before I solder it. Inside and out and I make sure there are no little black marks anywhere around where its going to be soldered. I make sure I don’t touch the joint after I clean it to keep the oils from my hands out the joint.
Got a tip from a plumber, don’t get the joint too hot. Use a propane torch in place of oxygen/acetylene torch.
Stay strong, write on. Professor Hyram Voltage