How to Plumb a Sink With Copper
- 1). Turn off water at the main shutoff valve and mark the existing hot/cold lines where you want to attach the new water lines--use a felt tip pen.
- 2). Place a tubing cutter around one water line, and tighten the blade onto the mark. Rotate the cutter and tighten a second time. Rotate again and repeat this process until the line is cut through. Do the same with the other line.
- 3). Sand the lines where you made the cuts, as well as the insides of two "T"-shaped copper couplings--use an emery cloth.
- 4). Apply soldering paste (flux) to all sanded areas with a small brush.
- 5). Push the cut pipes of both hot/cold lines into the ends of the "T"-shaped couplings.
- 6). Cut new pipe to the required length for both hot and cold lines: sand the ends and apply soldering paste as before, and push the pipes into the "T"-shaped couplings. Now cut all new pieces of line to length and prepare/install all necessary couplings along the predetermined route to the bottom of the sink.
- 7). Sand and paste two end caps and fit them onto the ends of the new lines.
- 8). Uncoil 12 inches of solder from its spool and bend the last two inches 90 degrees.
- 9). Turn on the propane torch and beginning at the "T"-shaped couplings, solder every new joint, as well as the two end caps: Hold the flame against the coupling, moving it from side to side. Do the same on the back side of the coupling and when you hear the flux sizzle, take the flame away.
- 10
Touch the seam between the coupling and pipe with the tip of the bent two inches of solder. If it melts, apply 3/4-inch of solder. Repeat this with the other seam(s) and wipe away excess solder with a rag. - 11
Turn the water back on, after all joints have cooled.
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