Making Brake History
A couple of weeks ago we here at Prime Choice kicked off our parting wisdom series with a look at the wheel. What good is a wheel if it can't be controlled? This week, parting wisdom looks at brake history and discovers how we started stopping our wheels.
Currently, the fastest production cars in the world are capable of traveling over 430km/h. At this speed, a vehicle would make the 100M dash is less than one second (the current human world record is just shy of 10 seconds). To further put it in perspective, a vehicle traveling at constant 430km/h could circumnavigate the earth in a little over 3 days. To quote Jeremy Clarkson "Speed has never killed anyone. Suddenly becoming stationary, that's what gets you". So how have we evolved from wooden brakes to performance carbon ceramic cross drilled rotors with semi-metallic pads? Take a break and learn some brake history with us.
As you already know, early vehicles featured wooden wheels with steel bands taking the place of modern tires. These vehicles weren't designed to travel fast, and weren't designed to stop fast either. Early brake history involved a wooden block attached to a lever. When needed, the lever would be pulled pressing the wooden block into the steel bands on the wheels. This method actually served to be useful, and was adopted for use on horse-drawn carriages and motor vehicles alike. It wasn't until the adoption of the rubber tire that this type of brake began to be phased out. Since slamming a wooden block into a spinning rubber tire was no longer an option, a new method of braking had to be designed.
To the beat of a different drum
After rubber tires were introduced, a new more reliable method of braking needed to be created. The next big leap in brake history came when, in 1900, Maybach (A former car producer, now an executive trim option on ultra-high end Mercedes vehicles) first introduced the drum brake to one of its models. The idea was tweaked slightly and patented in 1902 by Louis Renault, of the Renault car company. These early drum brakes were operated by cables and levers, and used a design similar to what we see today. Since there were no advanced composite metals available at the time, asbestos brake shoes were used.
You couldn't have brake history without the drum brake. A drum brake operates by having its pads or shoes located inside a drum that spins with the wheel. The shoes press against the inside of the drum when activated, creating friction and slowing the vehicle down. Over time, the technology changed from cables and levers to hydraulics and pedals. In 1918 the first use of hydraulic brake drum systems was invented by Malcom Loughead (who would later become cofounder of one of the most dynamic companies of all time and adopt the American spelling of his name, Lockheed). The hydraulic system used by Loughead had caught on to the mainstream of vehicle production by 1920.
For the next 50 years, drum brakes reigned as the definitive method of stopping a car. They received a few upgrades along the way, such as self-adjusting shoes (previous to 1950, drums would require frequent manual adjustments). Other compounds began being used for brake pads as asbestos was discovered to be damaging to personal health and safety. As time went on, it became apparent that with faster, more powerful engines, brake drums had some flaws. The design of brake drums allowed for poor performance at high heat, and became increasingly ineffective for the bigger engines being produced.
The Next Step In Brake History
Bigger engines mean bigger brakes. Drum brakes couldn't keep up with the performance of engines. In 1950, the Crosley Hot Shot was sold with a new feature, disc brakes. This early milestone in brake history wasn't perfect however. Early disc brakes has troubles performing in the snow and ice, or in areas where dirt buildup could take place. A popular option for Crosley Hot Shots was a drum brake conversion kit. It wasn't until 1953 that reliable, lower cost disc brakes were created by the Dunlop company for use on the Jaguar C-Type. This iteration of the disc brake caught on and became the standard for front wheels in cars. Many cars featured front disc brakes with rear drums. This was because front brakes do the majority of stopping, and disc brakes were more expensive than drums. In 1963 the first American production car, the Studebaker Avanti, was released with disc brakes. The Avanti set numerous speed records, breaking 29 records and the Bonneville salt flats.
Disc brakes become the new standard. This opened the door for all sorts of advancements in brake history. A disc brake works by having a set of brake pads clamp on to a disc that spins with the wheel. The advantages to disc brakes are less chances of the brakes sticking, and a better dissipation of heat. With newer brakes more capable than ever engines could continue to get bigger and bigger.
New brake rotors can feature a variety of advance science. High performance rotors are slotted and cross drilled, meaning there is plenty of room for heat to dissipate. The rotors themselves are made up of a carbon-ceramic alloy, and are attached to either semi-metallic or ceramic brake pads. A far cry from a wooden block on a stick. Modern brake systems also feature something known as regenerative braking, for use in electric vehicles. This takes some of the energy lost in braking and captures it back into usable power.
It's hard to see where the future of brakes will take us, but brake history is a perfect example of the incredible evolution we've made in just over 100 years. Stay tuned for more parting wisdom!