how does my caliper work

[Ishmael]

I'm not that stupid but I've never used this type of caliper and I can't figure out what pushes the pads back on my c5 front caliper.
How does that caliper work? Am I missing a part?

[MonzaRacer]

The actual design of the seals are what release the caliper after pressure is released. They are a square/rectangular cut seal set in a groove that isnt completely square with the piston bore, this makes the rubber seal twist so to speak, this allows the piston to be pulled back a few thousandths.
Where drum brakes have to move quite a lot and the drum can and does expand when heated and pressed, this allows drums to fade and give making them less able to stop and on top of that used to be we had huge drum brakes with super asbestos shoes, these could handle more heat and the large drum had more surface area to cool down.
Now reason why a disc brake stops better is that the disc cant go anywhere, its clamped, and the fins inside while it spins create a "vacuum " effect pulling cool air in.
where drum brakes may be moving around the thickness of say 3 or 4 sheets of paper at the most, drum brakes may have to move the thickness of a dime, (which if you would like to know is 0.032") with them having to move so much, your pedal goes farther down before the line pressure goes up to "stop" you foot from traveling. and if your rear drum brakes get worn and dont adjust this makes a low pedal, disc usually never have this issue.
Big thing to remember is use brake lubricant on the BACKS of the pads and anywhere the metal backing touches another piece of metal, just a thin coat and any sliders or sliding surfaces, simply spread some of the brake grease on, just dont get it on the rotor or the pad braking surface(used to work at autozone and had a mexican fella grease the actual pad surface, he just couldnt figure out why his care wouldnt stop, after he comes in, with his 10yr old daughter and she tells him he screwed up, she simply told him he needed to learn to speak and understand english, hmmmm out of the mouth of babes huh.
Good luck
Lee Abel
AFTERMARKET PERFORMANCE

[Ishmael]

Thanks Lee,
I understand how the actual disc brake works. I should have been more specific. I'm wondering how the corvette caliper works. Its different from a conventional caliper. I'm wondering how the pads move back out after the caliper has been released, what is holding them in place and why there are only pistons on one side?

[DarkoNova]

I'm not sure what kind of caliper C5's use, but the way you're describing it sounds like it's the sliding design. There should be a slider on each side of the piston. The caliper bracket mounts to the spindle, and the caliper itself mounts to the caliper bracket via the sliders. Basically when you hit the pedal, it moves the piston, which pushes the inside pad onto the rotor, but it also allows the caliper to move on the sliders, so it pulls the outside pad into the rotor.

As Monza mentioned, the seals retract the caliper when you let off the pedal.

EDIT: Yeah, just googled it, and it's the sliding kind. I forget what the name of that style caliper is, but it's a pretty common design used in tons of OEM disc setups.

EDIT 2: I thought they were floating calipers. Turns out I was right. :)

Matt

[Ishmael]

I get that when the piston retracts that lets the pressure off the pad on the piston side, the caliper slides over and lets the pressure off the other side pad but as far as I can tell from the parts I have, nothing is going to actually push the pads off the rotor- there just won't be pressure on them. I'm guessing that the pads just hopefully bounce off the rotor and won't ride on it. I just don't see what is going to keep the pad sitting evenly in the caliper and not riding the rotor. I've got three anti-rattle clips per caliper but not the spring clips that I would have on a normal caliper. Am I missing something or is this just so simple that I'm getting paranoid?

[DarkoNova]

IIRC, the pads are always touching the rotor, just very, very slightly.

Could be wrong, though.

Matt

[Apogee]

I get that when the piston retracts that lets the pressure off the pad on the piston side, the caliper slides over and lets the pressure off the other side pad but as far as I can tell from the parts I have, nothing is going to actually push the pads off the rotor- there just won't be pressure on them. I'm guessing that the pads just hopefully bounce off the rotor and won't ride on it. I just don't see what is going to keep the pad sitting evenly in the caliper and not riding the rotor. I've got three anti-rattle clips per caliper but not the spring clips that I would have on a normal caliper. Am I missing something or is this just so simple that I'm getting paranoid?

Scott...you're getting paranoid. It may be hard to believe, but they really are that simple. To answer your question, nothing pushes the pads off of the rotors, which is basically true of all floating calipers. The pads however shouldn't induce much drag so long as the calipers fully release and the pins slide freely in the pad abutment brackets.

Tobin
KORE3

[LSx_88_Ciera]

IIRC, the pads are always touching the rotor, just very, very slightly.

Could be wrong, though.

Matt

You would be correct provided the rotor and hub were 100% true with 0 runout which is quite uncommon. The runout throws the pads back ever so slightly and as the rotor/pads cool/contract you gain a bit more space. Even straight off a brake lathe you will still have some runout from the hub and/or the hub to rotor mating surfaces. Granted this is a very small amount of clearance but a .0001" gap is still a gap. Is there friction, yes but it is from wind sheer/fluid dynamics and that is over my head.

[Ishmael]

Thanks guys. That really is too easy.