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Soldering Copper Pipes

Last Updated on Saturday, 08 May 2010 18:34 Friday, 07 May 2010 17:00

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Articles - Soldering

SolderPasteInstalling new copper pipes in place of my old galvanized steel water lines, and need to know how to solder copper water lines without causing any damage and burning your house down with a blow torch? Here are some tips on fire safety.

Although jobs like this may seem too difficult for the homeowner to complete, you can get strong and lasting joints with just some information and know-how. We’ll also provide a couple of tips on reducing fire risks. See the video below for additional help.

You’ll need a tube cutter, round wire fitting brushes, plumbers sand cloth, flux, a flux brush, a torch (propane or acetylene), lead-free solder, and a few five gallon buckets. This short list of equipment is necessary to complete the job safely and orderly, and they all can be found at your local plumbing supply.

Tube cutters will put a clean cut in any copper tubing. Apply the sand cloth to the ends of the pipe, smoothing out the areas where the tube cutters incised the copper. Next, remove oxidation by rotating the fitting brushes inside the copper fittings.

Now it’s time to open up the flux container. There’s a solution inside the container, consisting of zinc chloride, ammonium chloride, and paraffin. Mix the flux well to make it a solid solution. Once it has been thoroughly mixed, use a flux brush to apply flux to the areas of copper pipe that have been cleaned. Be sure to keep the flux solution away from your eyes and mouth, as it is highly toxic.

After applying the flux, it’s time to join the pipe and fittings and begin soldering. Fire up the torch using a flint striker or match, and make sure it is adjusted to the point where there appears to be a small flame inside of a larger flame. Hold the tip of that inner flame to the point of intersection between the pipe and the fitting. That inner flame is the hottest part of the torch and will be most effective in soldering metals. The flux should begin boiling instantly.

It should take about ten to twenty seconds for the flux to disappear, at which point it is time to apply solder to the point where the pipe and fitting connect. It should begin melting into the fitting immediately, and once you see that it is melting, remove the torch from the pipe. Solder usually needs to be applied for about five seconds, although the pipe will probably retain enough heat to burn solder for an even ten seconds.

If your house has a wood frame, it is important to be very careful when using a propane or acetylene torch. Small bits like wood chips and paper insulation can catch fire very easily and spread at an exponential rate. Also, purchase a fire extinguisher that is designed for wood and paper fires. You can also utilize a flame-proof fire shield (flame resistant cloth from a home repair store) or even just a good-sized piece of sheet metal. Whatever you choose, place the metal piece between the copper and any flammable materials. The best safety tip is to be fully aware of your surroundings. Make sure that the torch flame is only soldering and not burning anything.

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