Pads & Rotor Information

[991.8l]

Great read.. I think I have this exact problem with my front rotors...

http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml#

[Hacker]

+1

My wife's Mazda3 occasionally gets the "warped rotor" feel. Whenever that happens, a few hard braking sessions on the highway usually solves the problem. I think this is equivalent to re-bedding the brakes (i.e. removing the uneven deposits and re-applying new pad material to the rotor surface). Just remember to not hold your foot on the brake pedal when the car comes to a stop. Otherwise the pads will be imprinted onto the hot rotors.

J.

[991.8l]

If only a small amount of material has been transferred i.e. if the vibration is just starting, vigorous scrubbing with garnet paper may remove the deposit. As many deposits are not visible, scrub the entire friction surfaces thoroughly. Do not use regular sand paper or emery cloth as the aluminum oxide abrasive material will permeate the cast iron surface and make the condition worse. Do not bead blast or sand blast the discs for the same reason.

Anyone know a good place to get Garnet Paper? Local paint store?

[dead_cactus]

Any place that sells woodworking supplies will have it.

[991.8l]

Any place that sells woodworking supplies will have it.

Maybe Rona then? :confused:

What about a place that will Blanchard ground discs?

The only fix for extensive uneven deposits involves dismounting the discs and having them Blanchard ground - not expensive, but inconvenient at best. A newly ground disc will require the same sort of bedding in process as a new disc. The trouble with this procedure is that if the grinding does not remove all of the cementite inclusions, as the disc wears the hard cementite will stand proud of the relatively soft disc and the thermal spiral starts over again. Unfortunately, the cementite is invisible to the naked eye.

[991.8l]

My front rotors on my Acura are pretty annoying, going to try the Garnet paper, then if that doesn't work replace them with new rotors and have the old ones machined at partsource for $25 each.

[991.8l]

Any place that sells woodworking supplies will have it.

Found it at Rona... $3 for a like 4-5 sheets, I got 220, 150, 100 grit.

[Mike_Moss]

^ Pics of it?

[dead_cactus]

Looks like sandpaper

[Mike_Moss]

Cool, I want to pick some of this stuff up. Always good to give the rotors a good wipe down when changing pads.

[991.8l]

Its on the bottom rack of all the sand paper.. big "GARNET" name on the front. Should say its for hardwood, cabinets etc. Don't bother asking someone that works there, they have no idea what it is.. lol.

Edit - Used the Garnet paper over the weekend.. used the medium grit, didn't accomplish much. Took the deposits off, but my rotors are too scored.. going to need resurfacing.

[vtec-this]

great link. gonna go do 10 hard stops now lol

[991.8l]

Has anyone ever had a shop check the hub and rotor run out before installing new rotors? I just picked up a pair of Brembo Rotors from Tirerack and it recommends I measure runout before install.. as there is no warranty on the disc once its been driven on.

http://www.ebcbrakes.com/automotive/check_brake_rotor_runout.shtml

http://www.vibratesoftware.com/html_help/html/Diagnosis/Tire/Axle_and_Hub_Runout.htm

Dealership can do it.. but its pricey to go there. One mechanic didn't have the runout dial indicator, another hadn't used it in years.

[Hacker]

I've never measured run out. I just make sure the hub area is very clean before installing the rotor. Brush/grind/sand off any rust before putting in the new rotor.

J.