https://www.brakeconnect.com/cunifer-brake-linesample quote
It is a material known as Cunifer – an alloy of copper and nickel with a bit of iron and manganese thrown in for good measure.
In the world of metallurgy, this material goes by the names of Copper-Nickel CA 706, Cupro Nickel 10%, and C70600 and, as mentioned Cunifer alloy. In actuality, the alloy consists of 88.7% cop-per (Cu), 10% nickel (NI) and 1.3% iron (Fe ),although I have seen specifications listing 0.8/0 manganese (Mn).
For those of you who are not chemists or metallurgists, the previous paragraph was probably wasted, but it is important in that this special alloy makes a wonderful substitute for the traditional steel brake tubes used on our cars.
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This alloy provided superior corrosion resistance to steel, was malleable, easy to work with and easy to flare, was strong and had most of the benefits of copper tubing without the liability of work hardening. The inclusion of the nickel, steel and manganese made it stronger than copper alone, but still short of the strength of steel.
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You can buy just what you need, flare it yourself and install it as easily as you would regular copper line.
When you buy it though make sure that you order the correct fittings for brakes. They ARE NOT the same as the plumbing fittings that you buy at the local home building center. Brake fittings require special flares at the ends. Compression fittings are NOT acceptable, nor are single flares. A double flare is much stronger than a single flare, and is not a lot more difficult to make.
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