Best Brake Line Flaring Tool

Most mechanics know that a high quality brake line flare can make all the difference. Yet, choosing the best flare can be a challenge. Flaring tools are manufactured in several types with different levels of quality. The flaring tool can aide in fitting brakes, transmission lines, and cooling and fuel lines. It can be difficult to find the tool that will work best. The use of flaring tools is closely associated with safety regulations, which makes the choice of tools an even bigger concern.

What are Flaring Tools?

Flaring tools (view on Amazon) are adaptive components which utilize pressure to make mechanical joints to seal the copper tubing with flare connections. The ends of the flare usually have a conical shape. These tools have been around for most of the history of metal working. The size of the tool is industry-specified.

Flaring tools consist of 3 primary components: a screw with handle which fits into the piping opening to expand it; a metal bar with holed presets to fit different tubes or pipes; and a metal component that fits into the handle to enable rotation. The types of flaring tools include block-type flaring tools, also known as screws. With the use of flaring, tubes or pipes can be connected to other tubes or pipes as well as to other types of fitting. The flaring comes in many designs: The flaring tool also comes as a cutting tool that can cut soft materials such as copper.

Bubble Flare – The bubble flare is used with a male swivel nut to seal the bottom of a tapped, drilled hole. The DIN/ISO bubble flare has the same components as the regular bubble flare; however, the ISO bubble flare has pipes and threads which are measured in metric units rather than inches. The bubble flare allows for resealing; however, bubble flares do not last as long as some other flares. If the end of the tubing resembles a button and the back side of the flare measures 90 degrees, then you have a DIN flare. These flares are really popular in Europe.

AN Flare – AN flares, also known as 37-degree single flares can be combined with a nut so that it can accept double flares. These flares are a flare fitting that uses a 37-degree flared tube to form the metal-to-metal seal. The AN threads are not the same for bolt and fittings. The bolt numbers refer to the diameter of the bolt.

45-degree Double Flare – 45 degree flares have a 37 degree thread type. The 45 degree double flare is male-threaded nut which connects to an outside diameter flared tube. The head of the flare is designed at a 45 degree angle. These double flares are used to help control the friction wear (galling) which results from cracking at the flare. The wing nut double flare is one of the most common used in automotive; especially in the United States. These parts are cheap but can be difficult to use and they cannot be interchanged.

Universal Hydraulic Flaring – These flares are simple to use as once they are assembled, you actually get one tool. Many flares fall into this category, to include the 45 degree flare. The universal is expensive. The hydraulic feature often causes an overflare in the brake lines and cannot flare stainless.

Eastwood Pro Flaring Tool – This flaring tool is a turret styled flare with removable dies and heads. The Pro is simple to use and will make the perfect flare every time. It can also flare stainless.

Metric and SAE flares are made using the same principles; however, they have different angles. The SAE double flare has a 45 degree angle. The metric flare uses a 37 degree angle. The flare junction uses the same flare on the male and female ends. When Metric and SAE flares are mixed it causes problems with the seal.

The flaring tool is rated by its ability to form a tight fitting. The price of the tools varies depending on if the tool is a single or a double. Coolant and fuel lines typically use single flare tools. These types of tools are generally cheaper and work faster. Yet, brake lines require a double flare due to the enormous pressure.

The Braking System

The braking system has several components that work together to control the slowing and stopping of your car. The brake line translates the pressure from your foot on the brake into power that can stop the car. Most braking systems use hydraulics that use the brake fluid to transfer the pressure. The brake fluid is kept in the master cylinder until it is transferred to the brake calipers through the brake lines. The pressure forces the brake calipers to clamp down on the brakes.

Heavier vehicles require more braking actions than smaller ones. Also, depending on how fast you are going when you try to stop, it may require more pressure and friction to stop the car. Automotive braking system designs are continuously becoming more complex. When problems arise in the braking system, the brake pad wear sensor or tab notifies the computer that something is out of order. The more modern electronic brake wear sensor does the same as the old without activating any squealing noises.

As cars are designed to go faster and the driver can do more things while the car is in motion, the more there is a need for braking, parking, and emergency brakes. The automotive braking system is not so simple and requires the contributions of many parts and brake fluid. The brake fluid is stored in the brake lines and presses the pistons and the brake pads together, which stops the wheels and rotors. The brake shoes are a part of the brake drum and they push kinetic energy to thermal energy.

The brake drums and shoes generate friction to support the stopping or slowing down. When the gas pedal is depressed, the brake boosters increase the applied pressure. A plunger inside the master cylinder pumps the brake fluid through brake lines to the brakes. The braking system must be air tight all of the time, with no leaks or intrusions. This is because over time, the brake fluid loses its moisture resistance which means it has begun to absorb water. Air even sometimes becomes trapped inside the brake fluid.

Brake Line Flares

Brake line flares are a bit more sophisticated than most others and require a professional judgement as to which is best to use. The flare pipe makes a seal by pushing two pipes together. The pipe ends are at an angle and the ends are male and female. The male end presses up against the female end to create the seal. Typical brake line applications have a hard line end at the union which is on the female end.

The hard line has the nut which applies the force needed to seal the junction. The junction contains the body, nut, sleeve and seal. The male end is the soft line. A brake pipe expands around the center. The mechanic adds the flare to the end of the brake line, widening the opening. Single flares cannot withstand the pressure in brake lines and will crack or leak.

Brake Line Leaks

The brake lines can leak for many reasons. Low quality flares will only make the problem worse. The brake master cylinder is the heart of the automatic braking system along with brake fluid. When every component of the brake master cylinder is not working at its best, problems arise which must be addressed. T When the rubber seals on the brake master cylinder wear out, the brake fluid can become contaminated.

The vale and piston seals inside the brake master cylinder are also important because they can start to leak after the car has been driven for many years. The flat sealing washer may have become hardened and fails to seal. The bore inside the master cylinder becomes corroded which causes leaks in the seals. No matter when the brake lines leak, it will mean more problems in the braking system over time.

Best Brake Line Flaring Tool

Automotive mechanics use both double and bubble flares in the brake lines. The most commonly used bubble brake line flares are the DIN/ISO bubble flare and the inverted double 45 degree flare. Most American and Asian cars have the double inverted 45 degree flare. Most European cars have the DIN flare.

The quality of the brake flare is very important. The materials used to make the parts affects the life cycle. When the flare is low quality, the brake fluid leaks which could cause brake failure. High quality flares are made with the best tools. The die and tubes should be easy to screw using the T-handle. The vise mount should be compatible, and the tool should be simple to use. High priced flares are worth the money. A great consideration is the level of comfort the tool has when it is used along with great operating capacity. The best brake line flaring tools for 2020 are as follows:

  1. TGR Professional – Flare types: Single, Double and Bubble; Die Blocks 3/16”, 5/16”, ¼”, and 3/8”.
  2. Eastwood 25304 – Flare types: Single, Double and Bubble; Die Blocks 3/16”, 5/16”, 1/4”, and 4.75mm
  3. Mastercool – Flare types: Single, Double and Bubble; Die Blocks 3/16”, 5/16”,1/4”, 3/8”, ½”, 4.75mm, 6mm, 8mm, and 10 mm
  4. OTC 6502 – Flare Types: Single, Double and Bubble; Die Blocks 3/16”, 5/16”, ¼”, and 3/8”, 4.75mm, 6mm, 8mm, and 10 mm
  5. ABN Bubble & Double – Flare types: bubble and double; Die Blocks: 3/16”, 5/16”, ¼”, and 3/8”, 4.75mm, 6mm, 8mm, and 10 mm
  6. Double Single flaring 37 degree Professional Brake Line Flare Die Tool Kit – Flare Type: Double Single; Die Blocks 3/16″, 1/4″, 5/16″ and 3/8″

Brake System Maintenance

Routine maintenance is a good way to prolong the life of the braking system. Modern cars are equipped with a brake warning light on the dash. The brake warning light activates when the brake fluid is low in the reservoir or there is a leak, the brake pads are worn, or the brakes need to be replaced. The braking system should be serviced routinely according to the manufacturer’s recommendation. The brake fluid can be inspected when the car goes in for an oil change. Making braking system adjustments is usually inexpensive. When the braking system is serviced, the brake dust is cleaned, the parts are lubricated, and if needed, they can be adjusted. If the vehicle is not inspected routinely, small problems escalate to major problems which are much more expensive to fix. Have your vehicle serviced as recommended by the manufacturer and make sure to have brakes inspected and all of the fluids checked.

If you want to avoid brake problems or other issues and save $100s of dollars that you’ll spend at the auto repair shop, you’ll need to service your vehicle often – you can use our mechanic-rated Auto Maintenance and Repair Manual to do this. It’s basically what mechanics use to go through your vehicle to check if there are any problems that need fixing. As soon as they notice the most minor problem, they’ll ask you to fork out some money even though it’s a problem you can fix yourself in minutes – the manual will teach you how to maintain your vehicle every few thousand miles and it’ll teach you how to fix minor problems that mechanics will ask you to pay for; saving you money in the long run.

A lot of our readers have the Auto Maintenance and Repair Manual printed on their garage wall and 92% of them haven’t visited the auto repair shop in the last year because they know what to do to avoid problems. All it takes is giving your vehicle a little attention every few thousand miles and you’ll never spend money at the workshop again.