brake boiling

If boiling your brake fluid is such a big deal, how come I've never seen any effort to isolate the fluid carrying component (the piston) from the heat generating component (the pads and disc) of a braking system?
Why are brakes always designed with the piston in direct contact with the brake pad?

It's All Fucked Shirt $22.14

Unattended Children Pitbull Club Shirt $21.68

It's All Fucked Shirt $22.14

  1. 2 months ago
    Anonymous

    What is this, a brake piston for ants?

    • 2 months ago
      Anonymous

      based brainlet can't see the piston is literally the same thing copy and pasted over but with a small rod in between to reduce heat transfer.

      • 2 months ago
        Anonymous

        Brakes need to be reliable and anything you do which adds more parts, more complicated parts, more seals, more working fluids makes them less reliable.

        Brakes overheating from racing? Slow the frick down moron, too bad.
        Normal brakes overheating? From what like driving down a mountain? This isn't 1975 anymore a modern brake system can handle it and doesn't need moronic shit.

        moronic brainlet doesn't understand surface area and force per unit area

        • 2 months ago
          Anonymous

          I really didn't think my drawing would be that hard to understand and yet; here you are....

          • 2 months ago
            Anonymous

            OP pic is self explanatory. It is moronic. So is OP.

            Happy April, fool.

          • 2 months ago
            Anonymous

            >it is moronic because I said so
            Thankyou for your contribution

          • 2 months ago
            Anonymous

            Explain what is described with the right side picture of an extended brake system. Explain what the drawing means.

            Otherwise, you're fricking stupid

          • 2 months ago
            Anonymous

            It was explained, but I will dumb it down further for you.
            >Left:
            a simplified drawing of a traditional single piston floating caliper
            >Right:
            that same drawing, with exactly the same piston, which has been moved over so that it actuates on a rod which serves to further isolate the fluid from the hot brake pad

          • 2 months ago
            Anonymous

            I'm not wasting my time explaining to you how force over surface area works or why a small rod would make brakes garbage, nor why a small rod would be a heated point of failure under what used to be a fluid boiling scenario.

            I have been correct in my immediate understanding and assertions,
            I am also correct that you, the fool, are moronic.

            Good day.

          • 2 months ago
            Anonymous

            Make it a medium rod then
            >NoOOOOooOOO IT CAN'T BE DONE IT'S IMPOSSIBLE
            There are a million ways brakes could be engineered to further isolate the fluid from the brake pad heat, my drawing is only a simplistic representation of the concept.

            The question is; why have I never seen such an attempt, if boiling fluid really is a problem?

          • 2 months ago
            Anonymous

            if you're so smart design it, patent it, prove the benefit, and sell it to part makers or get fucnding to make it a business yourself

            I'm telling you, the thing OP drew up is the most stupid shit possible. if it were that easy it would have already been used.

          • 2 months ago
            Anonymous

            >it's stupid because I said so
            >no I won't elaborate why
            Ok you can leave now

  2. 2 months ago
    Anonymous

    Who told you that its a big deal? It almost never happens.

    • 2 months ago
      Anonymous

      All the brake fluid bottles that advertise their SUPER PERFORMANCE HIGH TEMPERATURE BOILING POINT

      • 2 months ago
        Anonymous

        Anon, all brake fluids are made to the same specification depending on their DOT rating.
        It's just a marketing ploy. You're gonna get the same boiling temps in each DOT rating no matter what brand you go with.

        • 2 months ago
          Anonymous

          Not true. do some research. the wet boiling points are roughly the same but dry varies a lot

  3. 2 months ago
    Anonymous

    ita not a big deal outside of racing or really hard street driving continuously. Ive only seen it boil on cars doing said activities when either the fluid is old, or they have an E LSD that uses the brakes to simulate having a lsd. Just keep new fluid in your car and youre not gonna have an issue. also, if you have ever worked on a car you may have realised that almost all brake pads have a metal shim on the back plate between the pad and the piston

  4. 2 months ago
    Anonymous

    the piston would just absorb heat then pass it onto the fluid

    • 2 months ago
      Anonymous

      Obviously, so why are brake calipers not constructed in a way that reduces this heat transfer?
      (yes there are ways to reduce head transfer)

      • 2 months ago
        Anonymous

        because there are likely other considerations to take into account, such as the strength of the materials in the caliper, amongst other things
        >(yes there are ways to reduce head transfer)
        do elaborate, what were you thinking that could be applied to a brake caliper?

      • 2 months ago
        Anonymous

        for road legal use, the brakes how they are currently designed is not an issue.

        if it aint broken, dont fix it. who wants to waste r and d money on something that is not a problem?

  5. 2 months ago
    Anonymous

    because if you actually put heat into your brakes you can just put SRF in it and not care

  6. 2 months ago
    Anonymous

    what if they had a cored passage in the caliper to circulate coolant to a separate reservoir through an electric pump?

    • 2 months ago
      Anonymous

      Based German engineer

      • 2 months ago
        Anonymous

        brake change step 1: drain your coolant

    • 2 months ago
      Aspiring Investor

      Water cooler calipers are already a thing.

      • 2 months ago
        Anonymous

        >Water cooler calipers are already a thing.
        Kek aio brake calipers when

        • 2 months ago
          Anonymous

          RGB wheelwells are already here

          • 2 months ago
            Anonymous

            >RGB wheelwells are already here
            >Not overclocking your ecu bcm pcm and canbus
            Inb4 this is actually a thing it technically could be especially on teslas kek

  7. 2 months ago
    Anonymous

    Why not just have brake calipers with coolant passages?

  8. 2 months ago
    Anonymous

    the only time in my life i had brake fluid boil was when i had an exhaust leak that was spraying hot gasses on my brake lines which caused brake failure.

  9. 2 months ago
    Anonymous

    >no one has answered the question yet
    OP the engineers do take it into consideration. They isolate the piston from the pad with the use of non-conductive shims. They’re not always used, it depends on the application. Shims keep more heat in the pad, no shim puts more heat in the piston and fluid. I think putting physical distance between them like you did has many drawbacks but I’ll let you think that through.

  10. 2 months ago
    Anonymous

    Probably because the brake fluid acts as a heat sink, and improves performance of the brakes.

    • 2 months ago
      Anonymous

      Not transferring heat to the caliper & fluid means more heat stays in the rotor, which means glazing & warping the rotor will be more likely. The most important part of a braking system is taking as much heat out of the rotor as possible.

      I didn't think about heat transfer into the fluid being a good thing, and I still don't really think it is, but what you're saying is in line with what I pretty much figured - the brake fluid isn't the limiting factor of a braking system.
      If the fluid is boiling then the rotor and pads have probably gone far beyond their intended sustainable heat range anyway.

  11. 2 months ago
    Anonymous

    Less complexity means less things to go wrong.

    And there is often limited space between the wheel and suspension components, making the brake caliper a few inches deeper may not be possible in a lot of applications.

    Also boiling brake fluid is never really something that comes up on a road car, it mainly something you need to contend with in racing applications. And then it's handled quite well with better braking equipment and specialized brake fluids.

    • 2 months ago
      Anonymous

      Pictured is a single piston floating caliper - there's pretty much always a lot of clearance on the inside of a brake caliper because that's where the wheel is, especially on modern cars with high offset wheels.

  12. 2 months ago
    Anonymous

    Not transferring heat to the caliper & fluid means more heat stays in the rotor, which means glazing & warping the rotor will be more likely. The most important part of a braking system is taking as much heat out of the rotor as possible.

    • 2 months ago
      Anonymous

      actually not true, the rotor is the biggest heatsink you've got. Brake fluid has very little avenue to shed heat

      • 2 months ago
        Anonymous

        Of course it's the biggest heat sink in the braking system. What I'm saying is that the most important part of a braking system is getting that heat out of the rotor because the rotor can only retain so much energy before heat soaking. Which is why most cars use vented double disks now since they allow them to radiate the heat away faster than it accumulates in normal driving. If this was not the case then we'd still be using old single disk rotors as they're cheaper and lighter yet still provide the same amount of braking force.

        • 2 months ago
          Anonymous

          what do you think a heat sink does anon. it transfers heat into the atmosphere. nothing else is doing that nearly to the level of the rotor. if anything it's better for as much heat as possible to go into the rotor, because a huge portion of that energy get dissipated within a few moments of letting off the brakes. you certainly don't want to take up that energy with the caliper and fluid lol

          Well there's plenty of room on a single piston floating caliper.

          but if you have the lowest spec bottom barrel setup, why are you worrying about over-engineering it? single pot floating calipers are what you'd find on a 1980's dirt bike, not a modern high performance machine.

  13. 2 months ago
    Anonymous

    >HOLD ON

    • 2 months ago
      Anonymous

      Whatever thing you put in between the rotor and the fluid will transfer heat no matter how big you make it, it might take a bit longer but the transfer will still happen. In fact, a longer and bigger piston will increase heat soak considering there's a bigger surface area to cool down. Also add three fact that the caliper still has to be small enough to fit inside the rim and has to be short enough to articulate back and forth on the front wheels, a long piston means the rear of the caliper will be thick enough that it will start hitting suspension components, not to mention the brake line might twist and bend excessively.

      Only 29 posts later? I expected it to be the 4th post at the very least.

      • 2 months ago
        Anonymous

        Once again YES YOU CAN ISOLATE THINGS FROM HEAT
        Simply reducing the surface area between the components that are sharing heat and increasing the surface area to atmosphere on the component you wish to keep cool will have an effect.

        • 2 months ago
          Anonymous

          >increasing the surface area to atmosphere
          his post does mention indirectly that you canonly do this so much before running into space/clearance issues
          also you need to keep in mind that concentrating the heat onto just the rotor and pads isn't always a good thing.

          • 2 months ago
            Anonymous

            Yeah I ignored his space clearence moronation because for the 1 millionth time on a single piston floating caliper like pictured there is HEAPS OF ROOM ON THE INSIDE OF THE WHEEL

          • 2 months ago
            Anonymous

            that room may be for steering to ensure that nothing rubs or touches anything when the wheels are being turned.

          • 2 months ago
            Anonymous

            No mr wrenchlet, that area is completely clear because the wheel runs around the outside and high offset wheels of modern cars sit much farther in that the brake caliper.

          • 2 months ago
            Anonymous

            ok, ask the engineers that do work on this stuff why your system hasnt been used

          • 2 months ago
            Anonymous

            HEAPS of room he says. Now also consider this vehicle has new full pads, so subtract about half an inch for when the pads wear down and the caliper moves further inboard.

          • 2 months ago
            Anonymous

            Yes HEAPS of room

          • 2 months ago
            Anonymous

            Okay and what happens when you turn the wheel full lock to the left? Do you think cars run straight and never turn?

          • 2 months ago
            Anonymous

            Based wrenchlet has zero experience with mcpherson strut cars
            See how the brake line comes STRAIGHT OUT of the brake caliper? Do you know why it's not neatly tucked away with a 90 degree banjo or something?
            BECAUSE THERE'S NOTHING THERE FOR IT TO HIT

          • 2 months ago
            Anonymous

            What do you think is gonna happen when you add another 5 inches to the piston you moron? Not to mention in FWD / AWD cars it'll hit the axle that goes straight through the middle of the hub assembly.

          • 2 months ago
            Anonymous

            Then you put a 90 degree banjo on the brake line and take up the same amount of clearance space

          • 2 months ago
            Anonymous

            >add 5 inches worth of brake piston
            >remove a quarter inch of brake line by adding a 90 degree banjo
            >problem solved
            You do know most modern cars already have 90 degree banjo bolts on their calipers right? A picture of a clapped out modified S13 from the 80s won't represent most of the cars on the road today.

          • 2 months ago
            Anonymous

            Look at the picture again little wrenchlet boy
            There's the boss for the brake line sticking out of the piston, then there's the steel flare fitting on the end of the brake line, then there's at least a couple of inches of the flexible hose sticking out which would need to be clear from obstructions.

            There's HEAPS of room on the inside of that brake caliper, otherwise the brake line wouldn't be routed like that.

  14. 2 months ago
    Anonymous

    anyone who races knows this isn't really an issue. simply keep up on your fluids and there's no problem. and you should never boil anything with normal use. Even with an intermediary between the pad and piston, all you're doing is increasing resistance and the heat will eventually soak into those parts anyways. plus you wouldn't have enough room to make calipers that much larger on performance vehicles.

    • 2 months ago
      Anonymous

      I don't disagree with everything you've said but you're completely wrong about heat transfer.
      If you're only adding mass as your barrier to heat then that's true, but there are many engineering techniques that can reduce the amount of heat that is transferred from one point to another regardless exposure time. This is ESPECIALLY TRUE for objects that are exposed to open air, and even more evident for objects exposed to moving air.

      • 2 months ago
        Anonymous

        yes but you don't have room for that. and pistons are already designed to accomplish this. why do you think they're hollow? adding another layer will just decrease efficiency

        • 2 months ago
          Anonymous

          Well there's plenty of room on a single piston floating caliper.

        • 2 months ago
          Anonymous

          but thanks for bringing up the hollow pistons btw, I had forgotten that the piston is inverted like that.
          We can only assume the hollow piston reduces the heat transfer enough that the brake fluid is no longer a limiting factor, and if not they'd simply make the piston larger with a longer hollow section until that's true.

          I guess that settles it.

  15. 2 months ago
    Anonymous

    >add steel spacer between brake pad and hydraulics fluid
    >spacer compressed like a spring when compressed (young's modulus is directly related to heat transfer)
    >brake now requires even more pressure to be built up in order to overcome this effect
    It's that easy

  16. 2 months ago
    Anonymous

    >what are brake fluid coolers

  17. 2 months ago
    Anonymous

    >brake boiling
    where? track?

  18. 2 months ago
    Anonymous

    just get rid of hydrualic fluid and all vehicles will use air brakes now.
    you can now enjoy input lag and chasing leaks as fittings and lines get old/worn thru

  19. 2 months ago
    Anonymous

    >If boiling your brake fluid is such a big deal,

    It isn't on the street or for most racing. Who told you it was?

  20. 2 months ago
    Anonymous

    Because you'll melt the pads and set the brake pads on fire before the hydraulic fluid starts to boil. The main reason why brake fluid might boil is if it's filled with moisture, and only happens with old fluid that should be replaced.

  21. 2 months ago
    Anonymous

    Brake fluid doesn't get hot because it's near hot components.
    It gets hot because it's being compressed.

    • 2 months ago
      Anonymous

      you're moronic

    • 2 months ago
      Anonymous

      Here's some homework for you anon.
      Take a broom and wedge it onto your brake pedal.
      Now get out and touch your brake calliper.
      If your hypotheses is correct the brake should feel hot.

Your email address will not be published. Required fields are marked *