Q: While running an Ethernet cable along a baseboard, I drilled into the drywall and right through a small copper water pipe. A small spray of water actually shot out of the drilled hole! I cut through the drywall with my pocketknife to see what had happened, then plugged the hole with my finger until my wife shut off the water. What’s the best way to fix the pipe? – Bill in Providence, R.I.
A: Some do-it-yourselfers may suggest that you just slap a quick patching compound over the hole, let it set and leave it. But if you don’t want to have to come back in a few months and redo the patch (and likely replace the drywall again), consider replacing the damaged section of pipe completely.
For this column, I’ll describe using a compression fitting to repair the pipe. A traditional copper coupling requiring soldering is another good way to accomplish this, and I’m only leaving it out for space reasons.
Purchase a compression fitting repair kit at the home-improvement store. You’ll also need a pipe cutter and deburring tool, a hacksaw and miter box (as a backup), emery cloth, fine-grit sandpaper, tape measure and marking pencil.
To fix the drywall/wallboard you’ll need a piece of replacement drywall, one or two pieces of thin plywood, wood screws, drywall tape, putty and a putty knife, as well as matching wall paint.
Make sure the water is off and completely drain faucets near and below the damaged pipe. Using a box cutter or drywall knife, cut away the damaged drywall with a little extra to spare, creating a square or rectangular hole.
To place the compression fitting, follow the cut length requirements in the repair instructions. Measure the damaged pipe, then divide the measurement in half. Align the half-measurement on one side of the puncture and mark the cut point on that side, then repeat on the other side. (So the puncture sits in between the cut marks.)
Cut the damaged segment of pipe away using the pipe cutter. If the pipe is up against the wall, you may need to use a hacksaw instead, using a miter box to keep the cut perfectly straight. (A straight cut is critical to fitting the repair coupling snugly.)
Wrap emery cloth around one side of the cut pipe and twist five times or so until the pipe is shiny. Then clean the inside of the pipe with the deburring tool. Repeat on the other side of the cut pipe.
A marking gauge should be part of the repair kit. Use it now by sliding over one end of the cut pipe to mark the point at which the fitting should be. Repeat on the other side. Then, slide the slip end of the compression fitting over one pipe until it stops. On the other side, attach the disconnect clip to the fitting, and slide clip and fitting over the other cut pipe until it reaches the final mark that you made with the gauge.
Test the fitting by slowly turning on water to the pipe.
Patch the drywall by cutting a piece of wallboard to match the cut-out area. Attach a strip (or two if needed) of plywood behind the existing drywall with wood screws to create a base to attach the patch. Screw the patch to the plywood. Mask the cut lines with mesh drywall tape and smooth on putty; let dry 24-48 hours before painting.
HOME TIP: When turning water on after a shutoff, turn on all the faucets along the line to clear out air bubbles.
Send your questions or comments to firstname.lastname@example.org, or write This Is a Hammer, c/o King Features Weekly Service, P.O. Box 536475, Orlando, FL 32853-6475. © 2013 King Features Synd., Inc.