sweating

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Topic :How to Sweat Copper Pipe
Materials needed: a propane or MAPP torch emery cloth round wire brush lead-free solder soldering flux Flux brush or very small stiff paint brush Wet cloth rag tubing cutter the proper fittings Basics of soldering pipes: 1. Cut the section of pipe to length remembering to figure in an extra 3/8 " for each fitting being used. 2. Clean the ends of the pipe with emery cloth until shiny and burr free. 3. Clean the inside of the fittings with the round wire brush until shiny. 4. Test fit everything...then pull back apart. 5. Brush a small amount of soldering flux onto all pipe ends and on the inside of the fittings. 6. Re-fit everything together. 7. Use a pair of pliers or vice-grips to hold the section being soldered. NOTE: holding the pipe with a tool too close to the piece being soldered will result in a poor solder joint because the metal tool will act as a heat sink and draw heat away from the joint. Keep tools as far away from the joint as possible. 8. Using the torch, start heating the pipe one joint at a time. When the pipe is hot enough, touch the end of the solder to the seam of the joint. The solder should flow freely and suck into the joint. If it doesn't, keep heating until it does. 9. Wipe the solder joint with a wet towel to clean and set the joint. A properly soldered joint will have no voids in the solder line around the fitting. We recommend trying a few sample joints before starting your project. Solder one joint, then look it over. If the inside of the fitting shows solder drips and runs, then too much solder was used. If the outside of the joint looks patchy or has globs of solder stuck to it, then there wasn't enough heat applied to it. If the pipe or fitting appears scorched, burned, or blue, then too much flux was applied or the pipe was overheated. All of these problems could lead to leaks or failure of the joints. It is very important to solder the joints properly.
Pipes must be free of standing water before soldering. A pipe filled with water will not get hot enough to accept solder. If you are making a repair to a water line that was recently carrying water, you may have a problem getting the joint to take properly. This is due to the steam that is created when the pipe is heated. To correct this problem, there are two solutions: 1.) use a hotter torch 2.) ball up some white bread (remove the crust) and jam it into the section of pipe that has water in it, and solder as usual. Once complete, flush the bread out of the system by opening the closest faucet after removing the aerator on the faucet. The bread will have dissolved in the water, and will exit freely.
If you're doing any soldering inside be sure to keep a bucket of water handy just in case. A fire extinguisher would also be a good idea. Disclaimer: This site is designed to be a guide. It is impossible for us to cover all scenarios for everyone's homes. Information may be incomplete or altogether wrong for your application. There is no substitute for professional in-house help if at all unsure of what you're doing. We have gone to great lengths to provide accurate information on all topics. We are not responsible for any damage, injury, loss, or loss of life due to advice given on this site or via email. All materials contained within this site are copyright 1999-2001 Household-Helper.