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![garth2](themes/aaAle/images/interface/profile-pic-placeholder.47cf740a.png)
Is machining of the rotor necessary. Subject to minimum thickness, there is a discernable lip between where the pad contacts the rotor and the outer part of the disc, but the pad is about 50% worn. Is it now necessary to machine the discs, or wait until the pads need replacing. WOF is recent and brakes work OK, car has done 88K. Machining makes the disc thinner over its whole surface, is this wise or is the work just a have run by brake repairers. Eventually the discs become too thin to disperse heat and then need replacing. Please advise, thanks
![Anon](/assets/Uploads/_resampled/ScaleWidthWyI3NSJd/CMSThumbnail-SetWidth75-aa-avatar.png?m=1518003100)
If the brake performance isn't affected by the lip on the rotors and the disk thickness is within specifications (ask the mechanic who is working on the vehicle) then they shouldn’t be skimmed otherwise have the brake disks resurfaced or replaced, depending on the thickness, when the brake pads needs replacing. It is not a good idea to machine the rotors unnecessarily as this reduces their life but if it is necessary then they should be resurfaced to ensure the brake pads have a true surface to work on.
In some cases it can be more costly to skim the rotors than replacing them but you will need to ask this question from the dealer to ensure you are getting the best deal.
![garth2](themes/aaAle/images/interface/profile-pic-placeholder.47cf740a.png)
Thanks that is what I wanted to know, when to service the brakes and not when it is unnecessary