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Joining copper 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. Whatever type of fitting you use, the pipe must first be cut perfectly square.
  
• You can cut copper pipe with a fine toothed hacksaw, but it is easier and more accurate if you use a tube cutter. 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.
  
• To join copper pipes with a compression fitting, first remove the cap nut and slide it over the end of the pipe. Then slip the brass ring, known as an olive, onto the pipe.
  
• Push the pipe into the body of the fitting, slide the olive up to the fitting and hand tighten the nut. Now 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.
  
• For soldered joints, use pre-soldered fittings as these are easier to work with.
  
• Clean the cut ends of the pipes and the inside of the fitting to a bright finish, using wire wool. Apply a paste flux to the fitting and pipes, then push the parts together.
  
• Using a heatproof mat as a shield behind the fitting, evenly heat the joint with the flame of a gas blowtorch. As a rim of shiny solder appears around the ends of the fitting, remove the heat and leave the metal to cool.