Cutting & Joining Pipes

Most homes are plumbed with 15mm, 22mm and sometimes 28mm diameter copper pipe. Joining pipework is basic to all plumbing installations and many repairs.

Copper pipes can be joined with brass compression fittings or soldered capillary joints. You can cut copper pipe with a fine toothed hacksaw, but it is easier and more accurate if you use a tube cutter.

Whatever type of fitting you use, the pipe must first be cut perfectly square.

To cut a pipe, lightly clamp the cutter on the pipe, with the cutting wheel on the cut line. Rotate the cutter around the pipe, tightening it a little after each revolution, until the pipe is severed.

Remove burrs from inside the cut end, using the pointed reamer on the cutting tool or use a small half-round file.

Compression Fittings

To join copper pipes with a compression fitting:

Step 1

First remove the cap nut and slide it over the end of the pipe.

Step 2

Slip the brass ring, known as an olive, onto the pipe.

Step 3

Push the pipe into the body of the fitting, slide the olive up to the fitting and tighten the nut by hand.

Step 4

Tighten the nut fully with a pair of spanners, one to hold the body of the fitting, and the other the nut. Assemble the other half of the fitting in the same way.

Pre Soldered Joints

For soldered joints, use pre-soldered fittings as these are easier to work with:

Step 1

Clean the cut ends of the pipes and the inside of the fitting to a bright finish, using wire wool.

Step 2

Apply a paste flux to the fitting and pipes, then push the parts together.

Step 3

Using a heatproof mat as a shield behind the fitting, evenly heat the joint with the flame of a gas blowtorch until a rim of shiny solder appears around the ends of the fitting.

Step 4

Remove the heat and leave the metal to cool.