Whether a pipe is soft copper tubing or steel brake lines, instructions for pipe flaring are the same. You can purchase a flaring tool kit or rent one from a home improvement store or automotive repair shop. Flaring kits comes with a clamp to hold the pipe, gauges to measure the pipe length and a flaring tool with a conical tip that flares out the pipe end. In addition to the flaring tool, you will need to purchase flare fittings designed for the project you are tackling.
Slip a flare fitting over the edge of the pipe.
Match the pipe you're flaring with the holes along the clamp. The holes designate specific pipe diameters. Insert the pipe into the clamp. Tighten the wing nuts on the clamp to hold the pipe in place.
Place a gauge next to the pipe. The gauge has a step on the side that measures the length of pipe that should stick out from the clamp. Line the pipe up with the step.
Turn the gauge over. Insert the stem of the gauge into the pipe. Skip this step if you are working with copper plumbing.
Turn the flaring tool sideways so the clamp slides between the arches of the flaring tool. Turn the flare back so the cone is pointing toward the gauge.
Twist the bolt at the top of the flaring tool to tighten the conical tip down onto the gauge or pipe. Tighten the bolt until the tip presses into the gauge.
Loosen the bolt enough to remove the gauge from between the tip and the pipe. Tighten the bolt again, forcing the tip down into the pipe until it will go no further.
Release the flaring tool from the pipe and the clamp. Loosen the wing nuts and release the pipe from the clamp.
Pipes must have clean and straight cuts for a flaring tool to work efficiently. Pipe cutters are the easiest way to cut pipe and a deburring tool or inner/outer reamer can be used to shave off metal shavings and burs from around the cut edge. Center the flaring tool onto the pipe to prevent a crooked or off-centre flare that could break easily and lead to leaks.