Steve takes a look at brake discs.
Everybody knows that brake discs help stop your vehicle as and when required, but did you know there are different types of discs available offering varying degrees of stopping efficiency.
Most brake discs are made of iron and sit within a rotating spindle and work by converting kinetic energy (speed) into friction (heat) when the brake pads are applied to the discs. Disc brakes where introduced to vehicles due to their improved stopping potential and ability to be cooled a lot more efficiently by being exposed compared to drum brakes which were more restrictive and were more likely to suffer from brake fade. Here's a run through of the different types:
Solid Brake Disc
These solid iron discs are flat/smooth and are often found on smaller/lighter economy vehicles or older cars due to being cheap to replace and adequacy for stopping power. However, under excessive use the heat build up can cause the discs to warp which can be felt as a judder through the brake pedal.
Vented Brake Disc
This type of disc is also smooth in appearance but are vented in the centre thus improving the cooling ability of the brake disc and helping provide improved and consistent stopping power. Vented discs are currently the most popular type found on most modern vehicles and generally very reliable.
Drilled Brake Disc
As the name suggests these discs are not only vented, but also drilled to improve cooling and often found on modified or performance vehicles. Even though braking performance is greatly improved, these discs can fail by cracking around the drill holes due to excessive heat or over a long duration of use due to the fact the disc can contain less amount of heat over the surface area due to there being less metal to absorb heat. They also have the added benefit of being lighter which can help shorten the vehicles stopping distance.
Grooved Brake Disc
Similar to drilled discs, grooved discs vent heat away from the discs via the grooves and are also found on modified or performance vehicles but are often noisier than other types of discs and have a habit of wearing brake pads more often.
Drilled & Grooved combination Brake Disc
As the name suggests this type of disc combines both benefits/disadvantages of both drilled discs and grooved discs and are found on modified, performance or race vehicles.
Waved Edge Brake Disc
Compared to all other types of brake discs which are cylindrical, this type of brake disc has a waved edge which saves weight whilst not hampering stopping potential and is the most modern of brake disc design. Allegedly, they also improve cooling of the disc and are found on performance cars.
Dimpled Brake Disc
This type of disc also does not have a flat surface and is designed to help reduce heat whilst not compromising the integrity of the disc. Looking very similar to drilled discs, except the drill hasn't gone through the whole disc.
I hope you've found this guide useful. Please let us know your thoughts in the comments below.