5 easy fixes for plumbing disasters

How to solder copper pipe

Whether it’s repairing cracked pipes or adding new fixtures, knowing how to solder is a handy and money-saving skill to have.

Step 1 is measuring and cutting your pipe to length. Fit a pipe cutter over the pipe and tighten the thumbscrew at the base so that the blade snugs up to the copper. Spin the cutter completely around the pipe a couple times, then tighten slightly, repeating until the pipe is cut. Use the reamer on the cutter to remove any copper burrs inside the pipe.

Step 2 is to scour the edges of the pipe with aluminum-oxide paper and scrape inside your connector (in this case, a 90° copper elbow) with a fitting brush. Dry-fit all your pieces first, then pull them apart and apply flux (also known as solder paste) to the end of pipe and the connector you’re going to join first. Fit the connector onto the pipe, then turn on your torch. Apply the flame, moving it all around the joint. After about five seconds, dab the pipe with lead-free solder. You’re ready to go when the solder starts to melt. Touch the solder to the joint and watch as it is sucked in. Cool the joint with a damp rag and prep for the next connection. Once all your joints are soldered and cooled, cross your fingers and turn on the water.

Tips: In close quarters, use a woven ceramic heat shield ($25) or a product like Bernzomatic’s Cold Coat gel ($10) to prevent nearby inflammables from igniting. Also, since the water is off, you should keep a bucket of water or a fire extinguisher handy.

Water trickling down the line will prevent pipes from heating up enough to draw the solder. A piece of bread shoved into the pipe acts as a temporary plug that will eventually dissolve away.