Brake skimming

digweed

Anyone know where I can get this done, preferably on the car and in the Galway/Clare area. It's been parked up for a while and I think the discs are warped. Also does anyone know if its possible to do this for a bike to???

Thanks.
D. :cool:

JHMEG

The rust won't be more than surface deep and will be burnt off in no time.

On skimming, it's probably easier and more satisfactory to just replace the discs.

Captain Slow IRL

I don't think skimming will cure a warped disc, it's just used to take the lip off the edge of it.

If they were warped, you'd get a vibration through the steering wheel when you were braking - if it's only rust, as jhmeg said, bring it for a spin and work the pedal to take the rust off.

digweed

Had a feeling thats what was wrong, just a mechanically minded person said that I might be able to skim them, The vibration stops once I slow to 40ish or brake hard.

D.

JHMEG

Warped discs will vibrate the steering wheel when you're braking.

You're tyres could be out-of-round if the car wasn't on blocks, or your tracking might be off.

Mr.Diagnostic

Skimming on the car is the best way to true up disks, as long as it is done correctly.

If they are warped you will fell it through the pedal mainly.

Sorry, dont know who does it in the west.

barrymac

Any skilled engineer with a lathe can do it but you need to know the safe minimum thickness of the disc, if they are warped it could take a fair bit to bring them back to flat.

I've heard as well that a tiny skim can improve braking power by taking off a layer of case hardening caused by the carbon in the pads impregnating the steel making it harder and less grippy. Does this sound mythical or can someone second this?

landcruiserfj62

"The vibration stops once I slow to 40ish or brake hard."


it actually sounds more like a wheel balancing issue to me.

if..you are driving your car..you press the brake...you feel a shudder in you r brake pedal >>>> this would suggest your dics may be warped.

on the other hand..

if..you came back to your car..happend to notice rust on disc rotors...drove car and whilst driving above 40mph (as you mentioned) sudder in steering....slow down and shudder stops >>>this would suggest wheel balance issue caused by weights falling off wheel, or maybe you put an odd spare wheel on it or somthing like that.

Also, if your taking it to a "skilled engineer" rather than a motor trade professional, make sure he has the specifications for your rotors (discs). In my experiance, dont skim the discs if they are within 2mm of minimum wear. Garages with auto data information will be able to advise better than a "skilled engineer" imo

Run_to_da_hills

Brake disks can be skimmed on a lathe using a carbide tiped tool. Most machine shops wont touch them because of the libility attached and they can be awkward if theres is hard spots from overheating. It can only be done to the minimum tolerance, ie 8mm or 10mm usually stamped on the disk itself. It is only worth while doing it on classic / vintage cars or those that allow it, Some disks are just as cheap to buy a replacement in a factors.

2manyturbos

Can anybody recommend a good engineering outfit or two in the greater Dublin area?

I got mine done with a guy somewhere around Rathfarnham years ago, it was a great job and much cheaper than new discs. Now I have lost his contact details unfortunately.

Older classic cars are my thing, and it is not always cheap or even possible to get replacement discs.

Thanks.

Elessar

2manyturbos wrote: »

Can anybody recommend a good engineering outfit or two in the greater Dublin area?

I got mine done with a guy somewhere around Rathfarnham years ago, it was a great job and much cheaper than new discs. Now I have lost his contact details unfortunately.

Older classic cars are my thing, and it is not always cheap or even possible to get replacement discs.

Thanks.

I know AC cars do it now. www.accarsales.com

Moanin

Brake discs are very cheap now.I put a new set on my A4 a few months ago.It was only €50 ish for the pair.

I would put new ones on if I were you

2manyturbos

Thanks for the replies, the information is much appreciated.

Some of the cheaply available "spurious" discs around can have lower grade steel and will warp quickly under high heat and heavy braking. For that reason I am reluctant to buy something that looks to be a good cheap deal, but will warp quickly.

My car is both heavy and fast, so weakness in the brakes shows up pretty quickly.

If there is enough meat on the discs and if they can be skimmed at a reasonable price it can work out a better solution, at least for a year or so.

A friend in Scotland with connections in motorsport tells me that swapping over discs from one side to the other can help or eliminate brake judder. I have not tried this yet, but I offer it here for what it is worth, it could be a cheap solution for somebody here with the problem.