how do you solder copper pipes together ?
A couple other tips: - oxidized copper solders very poorly - thoroughly clean the inside and outside surfaces of the pipe and fittings with emery cloth, steel wool or a wire brush. - remove all traces of grease or oil from the pipes - flux needs some heat to 'activate' (begin its cleaning process.) Test fit all the fittings, disassemble them, apply flux to the soldering surfaces, reassemble, then apply heat to the fitting, not the pipe. - make sure the fittings are round - any out-of-round fittings or pipe will compromise the solder joint. Cut off the pipe at a point where it is round, or replace a damaged fitting. - For drinking water applications, the National Plumbing Code requires lead-free solder. This solder alloy melts at a higher heat than the obsolete eutectic (63%:37%) tin-lead alloys, so you should be using MAPP gas instead of propane torches for your soldering. - support both pipes from sagging or moving during the soldering and cool down process. Use bricks, stones, broken tiles, etc. to support the piples. Even wood can be used as long as it is far away from being burned. - a previous writer described the actual soldering exactly: you heat the metal (or fitting), and then flow the solder into the joint. You don't heat the solder. You can tell when the joint is heated to the correct temperature when the solder flows into the joint by capillary action. - if you overheat the copper, it will usually turn a dull red color after cooling. I would replace it at that point with new pipe or fittings.
the other answers are close, but not completely correct. the pieces need to fit together snug. they need to have no running water through them. if you have just a little water coming through than you can use a piece of bread minus the crust and ball it up and block the pipe. then you need to sand all of the fittings clean. then you need to apply flux to all of the fittings. then heat the fittings up and keep touching the solder to the fitting real quick until the solder starts to melt. then remove the heat. then feed in enough solder to fill the joint. approx. the same amount of solder as the size of pipe your repairing. 1/2 pipe equals 1/2 solder. you can tell when you have enough solder because you'll see it go completely around the fitting. remember that you do not want to over heat the fitting and that the solder will travel toward the heat. try to put the heat on one side of the fitting and apply the solder to the other side. i was told to sand your copper fittings until they shine like a new penny. I've been doing plumbing repairs and installations for 20yrs now and enjoy working with copper. i feel it holds up better over time. good luck with your plumbing project. mark
The number one secret to good soldering is proper cleaning the objects before you start. Obviously, use non-lead solder for a water pipe. Before starting, make sure all the water is out of the pipe. Any water near the joint will cause you not to be able to heat it enough. 1. Dry fit the pieces. Solder is not considered an acceptable mechanical bond, it just holds things together. 2.Sand the connection points with fine sandpaper that is made for this purpose. Be through. 3. Put flux on the connections. NEVER use acid flux on copper, use flux made for copper. 4. Put the pieces together. 5. Heat both sides of the connection, keep the torch moving all the time to heat uniformly. 6. When the pipe is hot enough to melt the solder, put it on the connection and heat both sides. Do not simply put the torch on the solder to melt it, the metal MUST be hot enough to melt the solder. Moving the torch slightly away from the joint and into the connector will pull the solder into the joint. 7. Be very patient while it cools. If you move it while it is too hot, it will give a bad joint. This is important. Be careful when applying the solder, some will drip off the connection. Wait until it is fairly cool before doing the other side of the connection so the first one does not remelt. This is a common problem. It isn't a big deal, but can make it harder to do.
