Here is the best way of joining copper pipe yourself. First, use fine sandpaper to clean the inside of the fittings and the ends of the pipes. Then brush flux onto your fittings. Join the pipes together and use a propane torch to heat the fitting (not the pipe). That pulls the solder into the joint. If the copper turns black, it’s too hot. Now wipe off the excess, and that’s all there is to it.
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