brake discs/'lip'

castle96

there is a lip on the o/side of each disc where the pads have bedded in/worn disc. Not dramatic and I see it on many cars. When I come to change the pads, surely the new ones will just sit in the same place and the lip won't be a problem ?
MOT failure ?
Did see on TV the other night (Wheeler Dealers) that there is a machine to take this lip off (in situ), though as any new pads will ? surely sit in the same place,, am I worrying about nothing ?

Ebe_Scrooge

A slight lip won't be an issue, it's when it becomes deeper that it starts to get more of a problem.

That said, on most cars new discs are cheap and easy to fit.

Sportacus

I think the MOT is just about the thickness of the pads and disc, so don't think a lip will be a problem.

As to needing to replace the discs, it depends how deep the lip is and how the thick the disc is. I made the mistake once of replacing my pads when the discs were nearly gone, within a few thousand miles I had to replace the discs - which meant a new set of pads too, grr!

colino

Lip won't be a problem as long as the brakes work properly. The sophisticated tool most techs use to remove it isn't the lovely on-car brake disc skimmer, its an angle grinder.

harveybobbles

colino wrote: »

Lip won't be a problem as long as the brakes work properly. The sophisticated tool most techs use to remove it isn't the lovely on-car brake disc skimmer, its an angle grinder.

Thats all I've ever used in the past lol

AdrianC

If it's just scale, then no need even to get that technical. A big blunt chisel or screwdriver against the caliper and rotate the disc to scrape it all off. WEAR EYE PROTECTION...

Iceweasel

I just go round the edge tapping it with a small hammer and all the scale/corrosion falls off.

Strider590

Or replace the discs at the same time.......

These days brake discs are considered a consumable item, no different to the pads.

gilbert_and_sullivan

How long is a piece of string?

The only way to know if the wear lip is too much is to measure the disc thickness and compare with the minimum disc thickness as stated by the maker.

The most important part of your car, arguably equal with tyres, should not just be guessed by someone unskilled.

Slowly_does_it..

Many moons ago I changed pads, and they were slightly bigger than the old ones. This caused the edges of the pads to just press on the lip until I wore the pads into shape. So very very poor brakes for 5km, so be warned!

Agree with others in this country, day and age. A set of discs is cheap, replace the discs if in any doubt.

mcjordi

if it passes the brake test on the MOT the tester generally doesnt care unless the disc is so cattle trucked they fail it