I am frustrated Because I Have Been practicing soldering 1 / 2 inch copper pipes at my building maintenance and running I cannot get it right. I got the outside from looking nice and neat goal when i saw the pipe down the middle and Separate the fitting and the pipe I see little round spots thesis (about 1 / 8 inch in diameter) Where the solder Did not stick. I Thoroughly clean the pipes, apply flux Enough, Enough apply heat and still I get like one or Two spots per pipe. What am I doing wrong? Thank you, Mario G. oh, and I apply aussi Enough solder. About 3 / 4 inch of solder for a 1 / 2 inch pipe.
