Doh - Brake pad inprint on disc. What now ?

[jade]

"Do not use regular sand paper or emery cloth as the aluminum oxide abrasive material"

There are lots of non-aluminum oxide abrasive papers on the market that will do the job.

Well that's good... he now has the correct info, and not to use emery paper like he was thinking

I do not think using a sanding disc and a drill is much off a recommendation

I think he is now pointed in the right direction

[stocious]

idk, the very thing they dont want you to use is actually used in the manufacture of brake pads.. look it up.

but thanks for bringing it to my attention.

ill keep it in mind

[CoupeWannabeS2]

I have had a few goes at trying to sort the problem out by doing brake runs. However I have been a bit paranoid about over doing it (don't want to make the problem worse). Last outing I was braking down from about 60 mph. It seems the inprint is disappearing, and the wobble is getting less when braking. So next time out, I will get the car up to a higher speed.

Plan is to follow the procedure detailed below that I have copied off of the site. Questions is can anyone advise how long I should drive the car for after doing 10 runs? I think I caused the original pad inprint by stopping the car in a layby too soon, and the pads cooked onto the disc. Would 10 minutes of dual carriage way driving be enough afterwards, or should I do more?

"Bedding in - The best thing to do is to find a long, straight, empty road (such as a country road between 2 quiet villages). Now perform 10 acceleration and braking runs, where you gently accelerate to a around 80MPH (theoretically you should slowly increase from 60 - 80+MPH according to the car and brakes) and then brake increasingly hard down to 5MPH. Never trigger the ABS, just aim to be at 95% braking on the last few runs.

Also NEVER STOP as you will leave a pad imprint on the disk surface - this is a life rule, not just for bedding in sessions - never sit at the lights with your foot on the brakes, if you braked hard and the brakes are hot. The pad imprint will cause brake judder that is often misdiagnosed as warped disks. In truth, it is virtually impossible to warp a modern disk!

The reason for accelerating slowly is to allow the brakes to half cool before the next stop. This puts the disks through a beautiful step up heat cycle, slow climbing until reaching the highest temp on the last run. You should notice a brake pad smell after the 2nd or 3rd run, which should have gone by the 7th-8th run. This is because you will have reached a high enough operating temp to have burned off all the surface contaminations and since the pad should now be 100% flush and therefore in contact with the disk, you will have transferred the pad material to the disk.

When you finish, the disks should be hot and a very even (slightly blue) colour across the entire contact surface. If for some reason there is still a small area of lack of pad contact, you can do a few more runs.

Believe me, this is the best way to bed in brakes as normal driving for 100 miles will not heat cycle the disk enough and will not generate enough heat to get a good transfer of pad material to the disk. It may also just not be enough to align the braking surfaces, particularly if you are not confident in the feel."

[Rusty]

I work on the principle that unless I can smell the brakes, they're not really working that hard. Crap pads will smoke but good kit should take a bit of heat without any issues.

[CoupeWannabeS2]

I work on the principle that unless I can smell the brakes, they're not really working that hard. Crap pads will smoke but good kit should take a bit of heat without any issues.

Thanks Rusty, I was just wanting to make sure I wont do any damage. I will be working them till I can smell them next time.

I have today found out a mate has access to a lathe at his work. So if my efforts with brake runs fail, I can get easily get them skimmed .