Brake discs skimming

[aramis]

Can we skim aftermart brake discs? I know for oem ones, it is not recommended to do so.

 

[absidian]

I think unless you have PCCB or carbon-ceramic discs then all discs whether oem or aftermarket can be skimmed to some extent. The deciding factor really is how much disc material (thickness) is remaining.

Is it brake judder that you are trying to eliminate?

Because technically, discs never actually "warp" as common knowledge suggests. It is usually the build up of brake deposits or pad glazing that creates an uneven surface. I usually do a few hard-stopping procedures from 60-20mph to clear this (whilst the brakes are already warmed up) and it usually works well. Doing this regularly, as well as not keeping a foot on the brake whilst stationary has eliminated any more need to skim any of my cars' brakes.

Hope this was useful... long technical blurb is really just a hazard of the job in my line! hehe.

 

[aramis]

yup, I had the irritating judder when I brake. Will do a few hard-stopping to see if it solve the problem. thanks again!

 

[moots]

Because technically, discs never actually "warp" as common knowledge suggests. It is usually the build up of brake deposits or pad glazing that creates an uneven surface.

Really?You have used a DTI test to confirm this?

Doing a stomp test once in a while to clear the deposits and glazing?Do we really need to do this as most drivers,me included,do this on a daily basis,to avoid frontal collision when idiot drivers brake to see accidents on the OTHER side of the highway,turn left or right without signalling,swerve left without warning to buy lemang etc etc.

Brake pad glazing happens when you ride your brakes.

My right rear disc was replaced because it WAS warped.How?The caliper piston was partially jammed and over time,the continous 'application' of brakes heated the disc up so much so that it warped.

A new disc and a repair of the jammed caliper piston (due to a brake hose acting up as a chk vlv) fixed the rumble upon brake application issue:burnout:

 

[chairoger]

Brake discs are relatively cheap. Just replace it if somethings wrong with it unless it happened too frequently.

 

[absidian]

moots, I understand what you are saying.... I think "daily stomp test" probably not enough la... this has to be repeated a few times in successsion. During normal driving - brake temps usually not enough to remove deposits. And must repeat few times in succession.

If the caliper jammed then, YES will possibly "warp" coz
a) the disc is subjected to high temperature over extended periods of time
b) uneven heat is being applied, i.e usually pad on only one side is jammed on
c) Excess heat from (a) will then cause the excessive pad glazing

I have had jammed calipers before, so what I usually do (diy) is remove them, clean/regrease the caliper's sliders, wind the piston back into the caliper and then swap the pads out for fresh ones. If the rubber boots and seals kaput then there is usually a "caliper refresh" kit available to replace them. Job's a good 'un

At the end of the day, my suggestion may not necessarily solve all cases of brake judder simply because there are many other factors involved... so just a suggestion that has worked for me and i'm just sharing it, k.


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