Plastic PVC pipes are often joined using a variety of non-threaded connectors. However, cutting threads into PVC pipes can facilitate connections to steel pipes. In addition, threaded connections create a more durable, leak-proof joint and are often desirable for sprinkler plumbing projects. Cutting threads into PVC requires somewhat expensive pipe threading tools. However, the results of your efforts are likely to be rewarding, and with a bit of practice you will be able to produce stable joints with minimal effort.
Things You'll Need
Thick-walled (i.e, schedule 80 - 120) PVC pipe - 1-inch diameter
Exposed ratchet threader handle
Thread-cutting die for 1-inch diameter pipe
Threader lubricating oil
2 bench-mounted pipe clamps
Insert the PVC pipe through both bench-mounted clamps. The pipe end should extend 8 to 9 inches beyond the clamp. Tighten the clamps to hold the pipe securely.
Place the thread-cutting die into the threader ratchet handle. The smooth edge of the die should face outward.
Slip the threader die over the end of the pipe to the point where it stops. The die is now engaged.
Oil the ratchet before beginning to cut pipe threads.
Hold the ratchet level as you slowly turn the handle clockwise to cut threads into the PVC pipe. Continue to turn until the pipe hits the base of the die.
Turn the ratchet handle counterclockwise to remove the die from the pipe. Take special care to hold the ratchet level as you make the final turns and remove the die.
Seal manually cut PVC threads with plumber's tape to ensure a well-sealed joint.
Instead of attempting to cut threads in PVC, simply attach a threaded connector using PVC primer and cement.
Never try to cut threads in thin-walled PVC pipe. The threads will likely break or the joint will leak.