How to Use a Brake Line Flaring Tool

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The brake flaring tool is one of the specialty tools that you should have if you do your auto repair all by yourself. Thanks to this tool, it helps you do a professional-looking job with transmission cooling line and brake line replacement.

Replacement of brake line would be a tough job without this tool because it’s nearly impossible to find the right length of steel line. Also, the tool will help you save some money on buying professional kits.

Today, we are going to learn how to use a brake line flaring tool. To guarantee that you have a good understanding of the subject matter, we have answered some relevant questions to get you familiar with this tool.

What Is a Brake Line?

It is a device that carries the brake fluid. Brake fluids are applied to transfer the braking power from a driver’s foot to the automobile’s brakes. Brake lines must be available and working because it is a crucial device that helps your vehicle stop when you need it.

A faulty or damaged brake line causes the brakes not to function at all or not function properly thereby, leading to accidents. Your vehicle’s brake system would fail to stop when needed, as a result of you lacking an adequately functioning brake line.

What Is Brake Line Flaring?

According to brake flaring is typically the process of widening the tubing of a brake line to ensure a leak-proof connection. If the tubing is wide, connection flows seamlessly and extensively, helping prevent leaks from happening.

Usually, brake lines that you buy at the store are mostly already flared at the ends. However, the degrees at which individuals want their brake line flared vary.

Hence, different vehicle types have different flaring degrees particular to them (you must find out which degree applies to your kind of vehicle). Therefore, you might need to flare your brake line some more after purchasing one.

What Is a Brake Line Flaring Tool?

Brake line flaring tools are adaptive tools used in brake pipes’ fittings; the tools provide a pressure-resistant leak-tight seal between soft steal. This process also is known as a forging operation.

These tools are employed in mechanical setups. It helps to have a perfect separable mechanical joint between two transmission pipes used in the brake for vehicles.

Brake line flaring tools consist of three main components which include:

  • Metal bar with a hole designed for different pipes
  • A screw that helps to expand the pipe opening
  • A handle that enables rotation by the user

Types of Brake Line Tools

brake line flaring tools are of three types which are:

  • Manual
  • Hydraulic
  • Leverage manual

Uses of Brake Line Flaring Tools

  1. These tools are used to fit brake pipes in an automobile and are often called the best pressure brake.
  2. Furthermore, flare tools are employed to fix cooling pipes to the compressor units of cars’ air conditions or refrigerators.
  3. Flare tools are also applied to fix two or more fuel pipes in vehicles, factory generators, and to avoid fuel leakage during operation.

Where Can I Find Brake Line Flaring Tools?

For example, on Amazon, you can find brake line flaring tools such as;

  • ARES 18020 – Double Flaring Tool Adapter Set – Use on Copper, Aluminum, Soft Steel Brake Line and Brass Tubing – Compatible 18019 Double Flaring Tool (at $13.12- $32.12)
  • Titan 51535 3/16-Inch Double Flaring Tool (at $42.95 – $55.24)
  • Shankly Flaring Tool Set (10 Piece – Professional Grade), Heavy Duty Steel Flaring Tools Kit and Swage Tool, Flaring Tool with Tubing Cutter Included (at $26.95)

Now, let us talk about how to flare a brake line!

To flair a brake line, you are going to need the following items;

  1. Brake lines
  2. A brake line flaring tool
  3. Other handy types of equipment for cutting, tightening, and so on. An example is a tubing clamp.

The following processes are steps that are required to flare your brake line:

  • Brake line usually comes in a fold. To start with, you are going to cut off a sufficing length of brake line from the fold.
  • Take the cap off to reveal the hole on the brake line.
  • Use a sharp object to wriggle the holes to enlarge the brake line’ s-hole. Put your brake line on the flaring tool (clasp).

NOTE: The inches of your brake line MUST be in synchronization with the inch side. For example, if you’re working with a 180-inch brake line, you must maintain that same inch with each equipment you use from the flaring toolbox.

In the course of this training, we assume that we are working with a 180-inch piece.

  • Get your 180-inch adaptor; the adaptor has two (2) hump sides. You need to line the adaptor and the brake line with the first hump. Make sure the brake line is even with the first hump.
  • Then, close up the clasp.
  • From inside your toolbox, get out your A-frame (in the form of the letter A-shaped).
  • Put your adaptor on the top of your brake line.
  • Now, put your A-frame on top of the adaptor and tighten so. Make sure it is placed in a straight form so you can get a subtle flare.
  • Twist your A-frame all the way.
  • Loosen your A-frame up and pull out your adaptor.

At this point, you have gotten a flared brake line.

Your brake line could be flared one time, or it could be double flared based on your requirement. After completing these lined-up processes, you should have a symmetrical looking brake line. That means you have successfully flared your brake lines.

How to Use a Brake Line Flaring Tool?

Before using a brake line flaring tool, you should first consider the tube’s size and the tube’s location. After that, the pipes’ material should be known to employ the type of flare that suits them.

Brake line flaring is done using either single or double flares.


  • Wear the proper safety gear.
  • Measure the brake line with a measuring tape.
  • Resize the brake tubing by cutting to the desired length with a hacksaw or tubing cutters.
  • Form the tubing flare using flaring tools
  • Cones of the tool should be positioned at the end of the tubing.
  • Move the cone until the tube’s part is flared using an advanced flare screw.
  • The new burst should be inspected for cracks, splits, or other imperfection.

Note: You should not use single flares on high-pressure lines, it is only best suited for low-pressure lines. They flare out just once in a conical shape and can easily crack or leak. Most vehicles use double flares which are best suited for high-pressure brake lines and also much stronger.

Final Thoughts

We hope this article helped show you how to use a brake line flaring tool. You don’t need technical skills to do this.  If you follow these simple steps, you will save some bucks on hiring an auto mechanic or buying any buying pre-bent kits.

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