How to Sand a Copper Pipe

Measure and mark to the required length two sections of copper pipe that will be soldered together. Place one pipe in the jaws of a tubing cutter, with the pipe resting against the two small rollers on one side of the cutter's jaws. Lower the small circular blade on the cutter's other jaw to the pipe, resting it on the mark. Rotate the cutter 360 degrees around the pipe, by hand. Tighten the cutter's blade to the pipe, and rotate the cutter again. Repeat these steps until the pipe is cut through. Cut the second pipe at the mark following the same process.

Tear off a 4-inch length of 120-grit emery cloth from its roll -- the cloth is roughly 1-inch wide, comes in rolls of various lengths and can be torn by hand or cut with a scissors.

Wrap the length of cloth around one pipe end, so that the cloth is perpendicular to the pipe. Hold the pipe and rotate the cloth several times around the pipe end. Remove the cloth from the pipe and look for any traces of dirt where the cloth was positioned. The pipe end should be shiny, free of dirt and have very light abrasive scratches. If any dirt still exists, clean the pipe end a second time. Clean one end of the second pipe in the same way.

Roll up the 4-inch length of emery cloth to a slightly smaller diameter than the diameter of the copper coupling -- make sure the emery is on the outside. Push the rolled cloth inside the coupling, turning the cloth several times to clean the coupling's inside. Remove the cloth, and look for any traces of dirt inside the coupling. If any dirt still exists, clean the coupling a second time.