Creating Custom Double Flared Brake Lines

Replacement brake, transmission and fuel lines are easy to create with a little practice and patience, paired with the right tools and knowledge from Eastwood. Follow along with us as we go through the process from start to finish.

Begin with an Eastwood OEM-style Brake, Transmission & Fuel Tubing Kit. These are available in 3/16", 1/4", 5/16" and 3/8" sizes, all with OEM-type, 0.028"-wall-thickness, corrosion-resistant, steel tubing; they include 25' of tubing and all required fittings. In this feature, as an example, we are using our Brake-Line Tubing Kit that includes 3/16" tubing and 16 flare fittings to create standard SAE double flare brake lines.

Using a tubing cutter, cut about four or five 1'-long tubing pieces for practice creating perfect flares. (Be sure to always remove burrs from inside and outside the tubing.)

Using our Professional Brake Tubing Flaring Tool or Universal Hydraulic Flaring Kit, select the 3/16" die set and, following tool instructions, place the end of the tubing in the clamping dies of the tool at the proper location, and tighten per instructions.

Place a very small amount of anti-seize compound on the face of the forming die to reduce effort, and eliminate galling and splitting of the tube end. (Always be sure to remove all traces of anti-seize before placing brake line in service, to avoid contamination.)

Depending on which tool you choose, carefully follow the forming sequence instructions, and then remove the tool and inspect the finished flare. It should be evenly formed with a smooth double flare (tubing will be folded back over itself inside a 45° conical shape) with no cracks.

Don't be discouraged if your flare isn't quite perfect at first. After several more practice tries with the pre-cut sections, you WILL be creating perfect flares worth boasting about! With confidence, you're now ready to create a replacement brake line complete with all factory bends.

Begin by measuring the length of line required, using the original damaged line as a guide (if available). Measure all runs and bends in the old line and add the figures to get the final length. (If not sure, it's better to overestimate and have a longer piece than a shorter line that won't fit). If an old line is not available, or you're constructing from scratch, purchase some inexpensive lengths of 1/8" mild steel rod at your local home supply store to plan where your finished line will go, and make a template for your finished line. Using this template as a guide, measure all the runs and total the figure as previously described.

IMPORTANT DETAIL: Be sure to first place the fittings on the line with the open ends facing outward. Then create your flares.

Slide and keep the fittings over the finished flares, and, using the old line or a wire template as a guide, begin your bends, starting near the center and working outward using the Eastwood Pro Former Tubing Bender to make all major bends. Trial-fit your piece frequently and use the Eastwood Brake Line Forming Tool to make final minor tweaks and bends. Attach the finished line to the brake components, add fluid and test for leaks.

Congratulations, you are now a professional!

As always, Eastwood offers the hobbyist the latest and best in equipment and supplies to help make that prized automotive possession the best it can be.