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Brake Line Basics
Walton Fabrication Shows You the Right Way to Bend and Flare Brake Lines
By Jeremy Cook
Many of us will go to great lengths (pun intended) to keep from having to bend up and flare a new piece of tubing. How many times have you seen a fuel line that goes from rubber to metal to rubber to metal to rubber? While you might be able to get away with patchwork like that in your fuel system due to the relatively low pressures involved, your brake lines are a different story. Disc brakes require about 1,000 lbs of pressure, and the drums use about 300 lbs--leaving no room for poor fitment or bad connections.
We recently dropped in on Todd Walton and the crew at Walton Fabrication to watch some expert line-fitting in action. And having since done some bending myself, I can definitely say that it's more rewarding than finding a short in your wiring.
A step that is often overlooked is de-burring both the outer and inner edges of the tubing. A quick hit with the file is all the outside edge needs.
A 1/2-inch countersink drill bit is used to quickly clean up the inner edge of the tubing.
Here's how a standard 45-degree double or inverted flaring tool works. Unless you're using stainless lines and A/N fittings throughout, this has been the standard since the '30s. First, make sure the fitting you're using is already in place on the line. Then the tubing is secured in the bar with the section of tubing protruding equal to the height of the die you're about to use.
With the die inserted into the tubing, the screw cone is compressed until the die is flush with the tubing bar.
The die was removed, and the screw cone was screwed directly onto the top of the tubing.
With the correct flare of one end of our line, we proceeded to the bends. To maintain the proper length, always work from one end of the line to the other. As you work, try to visualize the fact that with every flare and bend, you're pulling the line in slightly. This is how people get into trouble and miss their mark.
