The Art of Brake Pads: A Deep Dive

As we navigate the complexities of modern vehicles, it's easy to overlook the humble brake pad. However, these small but crucial components play a significant role in ensuring our safety on the road. In this article, we'll delve into the world of brake pads, exploring their various types, materials, and applications.

A Visit to the Brake Pad Store

One day, I walked into a store that specialized in brake pads. The sales associate asked me what kind I wanted, and I replied, "Can I get a brake pad, please?" The associate responded with a question, "Okay, what kind?" To which I responded, "I'm gonna cut it open, so." The associate smiled and said, "Wonderful." That's spelled B-R-A-K-E. Thank you. Welcome. See you in a week. Alright.

As the sales associate began to prepare my brake pad, I couldn't help but notice the array of different materials on display. "That's spelled B-R-A-K-E," the associate said with a chuckle. I smiled and replied, "Thank you." The associate then handed me the brake pad, which was labeled as organic. Anthony, the store owner, explained that these pads were made from a mix of various materials.

Cutting Open the Brake Pad

To understand the properties of the brake pad, we decided to cut it open and examine its composition. With an electric saw, we carefully sliced through the pad's surface, revealing its inner layers. The associate exclaimed, "Drill baby drill!" as we began our incision.

The Composition of Brake Pads

As we delved deeper into the brake pad, we discovered that it was a mix of different materials. The associate explained that this type of brake pad is made from anywhere between 30 to 65% metal, including steel and iron. The remaining portion is comprised of friction modifiers, such as fillers, resins, and graphite lubricants. These materials bond together, dissipating heat and providing a high level of performance.

The Chamfer: A Design Feature

As we examined the brake pad's edge, we noticed an angled cut – a chamfer. The associate explained that this design feature controls how the pad reacts when pressed against the rotor. By creating the largest amount of surface area touching the rotor, the chamfer reduces vibration and noise.

A Conversation with Eddy

Just as we were about to conclude our examination of the brake pad, a fellow mechanic, Eddy, burst into the store. He exclaimed, "Uh-uh!" as he attempted to return his own brake pad. The associate chuckled and said, "Sure feels like no one." Eddy replied, "You know, I had gotten these out of the back." The associate smiled and handed him a new semi-metallic brake pad.

A Comparison of Brake Pad Materials

As we began to examine the semi-metallic brake pad, I couldn't help but notice its differences from the organic pad. "Sure feels like no one," Eddy said with a chuckle as he took his new brake pad. The associate smiled and handed me the same type of brake pad. With an electric saw, we carefully sliced through the surface, revealing its inner layers.

The Performance of Semi-Metallic Brake Pads

As we examined the semi-metallic brake pad's properties, we discovered that it had a slightly higher level of metallic components than the organic pad. The associate explained that this difference in material composition would likely affect the pad's performance and lifespan. With a new blade and pad, we began to cut through the surface, observing how quickly the saw could penetrate.

The Limitations of Brake Pads

As we delved deeper into our examination of brake pads, we encountered some inherent limitations. Dust and hot gases produced by superheated pads can be detrimental to their performance and lifespan. The associate explained that these issues can arise due to excessive heat buildup or debris on the surface of the rotor.

The Role of Slots in Brake Pads

To mitigate this issue, manufacturers often incorporate slots into brake pads. These small openings allow dust and hot gases to escape without causing pressure or extra heat. By reducing friction and vibration, slots also contribute to quieter brakes.

A New Car and a New Set of Brakes

As Eddy left the store with his new semi-metallic brake pad, I couldn't help but feel a sense of satisfaction. He had traded in his old luxury car for a high-end sports car – boy, was that thing fast! However, the mechanic's words echoed in my mind: "You know, I had gotten these out of the back." It seemed that sometimes, even with new brake pads, it's essential to be mindful of our own limitations.

In conclusion, brake pads are more than just a simple component; they're an intricate system designed to ensure our safety on the road. By understanding their various types, materials, and applications, we can appreciate the complexity of modern vehicles and make informed decisions when it comes to maintenance and repair.

WEBVTTKind: captionsLanguage: en- Picture this, it'sa beautiful day and you'recruising down the road.Happy to be out of the office.And you're hugging the turnsand you're gaining speedand you're going down hill.Now you're going so fast that you can'tgo, slow down, somebody stop me!(exhales)Brake Pads!(fun music)Some people say brakesare just as importantas your engine.There I said it.Geesh. It feels good toget that off my chest.Without brakes, you don't just crash intoeach other all the time.Well it sounds pretty fun.Doesn't make much sense ifyou're trying not to be dead.Most of us have disc brakes on the car.But the disc is only half ofwhat's needed to stop your car.The other half is the pad.So as technology advances,the materials we use forbrake pads changes drastically.Bertha Benz, MercedesBenz fame gets creditfor inventing the first brakepads and they were leather.That was in 1888.The first disc brakesused in production werein a car made in 1902 bythe Lanchester Company.It had thin copper padsthat wore down quicklyfrom dust and dirt and reallythey were pretty useless.The idea didn't reallycatch on 'till 50 yearslater when the Jaguarteam won the 1953 Le Mans.Demonstrating thesuperiority of disc brakesover drum brakes.So, the brake pad or shoeas it's sometimes calledis made up of the asolid metal backing witha brake lining.Which is relativelysoft, but tough materialwith high coefficient of dynamic friction.The job of the brake pad is to convertthe kinetic energy of the vehicleto thermal energy through friction.When the driver presses on the paddle,two brake pad contained in the caliberare hydraulicallyclamped around the rotor.Nope.Think of a crab, pinchinga spinning quarter.When the pads come intocontact with rotor,they create heat.And that results in an small amount ofresidual material being left on the disc.This material allowsthe pads and the rotorto stick together.Brakes create friction in one of two ways.Abrasive friction andadherent or adhesive friction.Thinking about abrasivefriction, let's moveaway from brake pads and thinkinstead about sand paper.You know why sand paper is abrasive,it's because it wearsdown what it's rubbing.On the other hand whenthe brake pad comes intocontact with the rotor,that abrasive frictioncauses a lot of heat andis pretty destructive.It gradually wears down the rotor.Adherent friction is what happens when athin layer of the brakepad bonds to the rotorthrough the process of heat and friction.When the brake pad presses on rotor,it essentially sticksto the residue that isleft on the surface.Higher end brake pad, usemore adherent frictionbecause it's less destructiveand the rotors last longer.Alright, dynamic frictioncoefficient is measurementof how effective a brake is.We talk about the forceson the pad and thenthe force on the rotor.The force on the rotorscalled brake force.To figure out the dynamicfriction coefficient,we're gonna compare the two.If the brake puts aforce of a 1,000 newtonson the pad and the resulting brake forceis 400 newtons then thedynamic friction coefficientor DFC is .4.A normal commercial brakepad has a dynamic frictioncoefficient around .35 to .42.Some high end racingbrake pads can achievea DFC of of .62.And that's keeping a lot more force.Most consumer brakepads have a cool featurecalled a warning tang.And as we know, thewarning tang clan ain'tnothing to mess with.So if your break pad's worn down,these little metal stripswill scratch againstthe rotor and let youknow in the most annoyingway possible that you need new brake pads.Materials used to makelinings on brake padshave evolved to be the mostdurable, most efficient,most brake paddy.The materials must be ableto withstand extremelyhigh temperatures andtons of friction in orderto function properly.Asbestos used to be used inbrake pads for a long timebecause of it's ability todissipate heat extremely well.It's since been discontinued due to it'sharmful effects on health.Asbestos has harmful effects on health?Now you tell me.(cough)Modern day break pads comein many different types,depending on how durableyou need them to beor how much you wanna spend.There's four common categoriesof brake pad linings.Organic.Semi-Metallic.Full metallic.And ceramic.Some are so expensivethere usually only reservedfor race cars, or DJ Khaled.So, you got an old car that needs brakes.And you don't reallyfeel like sinking a lotof money into it.Organic brake pads.Sound great.These brake liners aremade of materials likeglass, kevlar, fiber, rubber, and resin.Because all those compoundscan withstand high heatand they're relativelyinexpensive to produce.The heat actually helps the materials bondtogether tighter.You wanna know the coolest thingin a lot of organic break pads?Cashew.Cashew containing frictiondust has the abilityto absorb the heat created by frictionwhile retaining breaking efficiency.Organic break pads were designed as analternative to asbestos pads.They're quiet, they'reeasy on the brake rotors,and one of the softer break pad materials.They don't need much heatto generate good frictionand they produce a minimalamount of break dust.There's a couple ofdownsides, but that's lifeget used to it!Organic brake pads wear morequickly than other brake pads.They also have a highcompressibility, because oftheir softness, whichcan cause a mushy feelingwhile braking.It's gonna lose some of that brake force.And that's why its got a lowerdynamic friction coefficient.But for normal use you stillget a pretty good brakefor your buck.- You suck!- It's a funny joke.Alright, now let's cut oneopen to see what it's made of.- Uh, we didn't get the pad yet.- Hey, what I gottado everything around here?- Sorry.- (chuckles)(swoosh)(typing)Hey, what's up Buddy? How you doing?- Oh, hey. You knowI watch one of your shows.- Yeah? What'd you think?- Eh, you spelled Diesel wrong.- (sighs) I know.- Anyway,what could I do for you?- Can I get a brake pad please.- Okay, what kind?- I'm gonna cut it open, so.- Oh okay, I'll be right back.Got your brake pad for you right here.- Wonderful.- That's spelled B-R-A-K-E.- Thank you.- Welcome.- See you in a week.- Alright.(swoosh)- Okay, So Anthony just sold mesome organic brake pads.We're gonna cut it openand see what it looks like.And how long it takes to do so.(electric saw)We're almost there.- Drill baby drill!(electric saw)- So again, it'sa mix of a bunch ofdifferent stuff.But we got through it pretty quickly.I'm excited to see howthe speed at which we cutthrough the pad is gonna compare with theother two types of padswe're gonna cut into.So if you've never seen abrake pad, you've probablynoticed that there's alittle angle on the edge.Zack get out of the lab.That's a chamfer, let's talk about that.If the surface of the brake lining is notperfectly aligned withthe surface of the rotorit could cause some problems.And that could be becauseof debris or maybeit was installed improperly.The extra vibration usuallytranslates into more noise.One way engineers dealwith this when the designthe brake pad is through chamfers.A chamfer is an angledcut on either end of thepad that controls how theedge of the pad reactswhen it's pressed against the rotor.This cut ensures thelargest amount of surfacearea touching the rotor,cutting down vibration.And in turn, cutting down noise.Okay, so you got rid of your old beater.You traded up for anice midsize luxury car.Good for you!You got a good deal,but it needs new brakes.You wanna spend a littlemore on your pads.So you go with semi-metallic.These brake pads are madeup of anywhere between30 to 65% metal.Like steel, iron, theseare tough metals thatcan handle a lot of heat.And the rest is made upof friction modifiers.Like fillers and resins aswell as graphite lubricant.These are materials that bond together anddissipate heat well.These are arguably the mostversatile of brake pads.They last a long time and provide betterperformance than organic pads.They do however, producea little more noiseand a little more dust.Wait, now let's cut one open.Eddy! Give me the semi-metallic brake pad.- Uh.- I swear to God!Eddy, If I gotta go back,this guy is gonna think I'm an idiot.(swoosh)Hey, me again Anthony.I'm hoping I can return this,I'm looking for somethinga little bit more high performance.- Oh, totally.Returns are easy and simple.- Sure feels like no one.- You know, I hadget these out of the back.- Thanks man, I appreciate it.- You're welcome.(whoosh)- Sure feelslike no one, doesn't it?Think he's got a brother?Anyways, Anthony giveme this semi-metallicbrake pad.This type of brake padgot a little bit higherlevel of metallic components,so we're gonna do what we do.So I got a new blade andand a new pad, let's seehow it does.(electric saw)Got it!This is a semi-metallic, and it did takea little bit longer thanthe organic to get through,this top part 'till we got to the sparks.You can see a slight difference.Down here, that's thetang, so if you hit thatit's gonna squeal, by design.That means you need new brakes.It's cool man, pretty sick.Somethings that areunavoidable when it comes toany type of break pad are dust and the gasproduced by super heated pads.There's no way around it.Like your mom in an hallway.These things can bedetrimental for brake pads,causing a drop in efficiencyand lopsided wear.If too much gas buildsup, the pads aren't gonnaget a solid contact with the rotor.Remember, we're turning kineticenergy into thermal energy.And if the brakes can'tdissipate the heat,then they get too hot, theycan't stop the kinetic energy.(slot machines)Slots in the break padslets the dust and hot gasesescape with out causingpressure or extra heat.They can also relievesome friction and reducevibration and that means,quieter brakes!And now wouldn't youknow it, you get boredwith that luxury car.You trade it in for a high end sports car.Boy! That thing is fast.But the mechanic says,"It needs new brakes."(chuckles)Can't catch a break!Am I right? Alright.This time you decide toshell out some serious cashfor some brake pads.So you go with ceramic.Ceramic just means asolid inorganic compound.Like a brick or porcelain.This type of pad has alonger life than organicand semi-metallic pads.It's also pretty quietand the dust they produceis light and doesn't stick to wheels.The downside is that ceramicpads are super expensive.Let's cut one of those open!Eddy! So help me gosh, ifthere isn't a ceramic break padin this office I'm gonna be upset!- (growns)- Oh man, oh man!(grunts)(whoosh)- Do you actually think he's mad?- Yeah, I thinkhe's mad I've never seenhim like this.- No, he's not mad,Bart doesn't get mad.- How was I supposed to know?- I don't know.Eddy I think you reallydropped the ball on this.- Oh, you knowwhat? I just found it.I have the ceramic pad.- He's gonna be pissed!- (grunts) Whatdo you want me to do?- Get rid of it!- (grunts)(shatters)- Just be cool, act normal. (whoosh)- I'm sorry guys, thatwasn't that big of a deal.I kind of flew off the handle.No harm, no foul.So this is a higherperformance, ceramic brake.It's a little bit different composition.I got a new blade, newbrake pad, let's see--(phone ringing)Hold on.Hello?It's Pep Boys.Anthony, how you doing?Oh, yeah I, no I, I forgotI actually cut that in half.Okay.Same card, just put it on the same card.Yeah, alright.Well, see you soon buddy.(electric saw)See it looks like there'sactually a little bitmore copper.So as you can see, cutting into it,I think it came apart pretty quick.'Cause all these brakesare designed to wear.You want the brake to wear not the rotor.Brake pad.There are of course,other type of brake padsthat we didn't cover.Full metal brake pads are just that.They're fully metal,but as you can imaginethey're not very good for daily use.Imagine metal on metal,you know that's bad.Right?Oh, but then we can't finish an episodewithout talking about theholy grail of brake pads.Carbon ceramic.These pads are the best when it comes toperformance, weight, andthe ability to handle heat.They comes standard on veryfew high end production cars.But, they're common indrag racing and aviation.When things are going sosuper fast that they needto stop even super-er more quick.I'm not gonna cut one openbecause I can't affordone of the dang old things.Carbon fiber brakes canupward cost upward of 10,000.That's more than my house.I live in a shipping container.This button is a subscription button.You know where you don't need brakes?Drag racing in a desert.What a dumb idea.Check out this video, it's rad.We got new stuff comingout, if it's the holidaysyou need to go toshop.donut.media, follow us onTwitter and Instagram @donutmedia.And follow me @bidsbarto,I take pictures of stuffand tell stories.Don't tell my wife Iforgot to pay for thatstuff at Pep Boys. (laughs)