Went and got my discs skimmed during the week after 'sensing a bit of judddddder' on the RallyDay sessions ... Seemed to be getting worse, I think it was starting to be felt on some bits of the journey to work. So off I went... Lookin' good... Really nice guys at 'The Garage Blackpool' - Thanks I got a strange whizzing/whirring sound whilst braking - sounds like multiple firework rocket taking off if you know what I mean... Thought it would disappear as the brakes bedded in... But it's been 3 days now - not been doing hard braking yet just teking it easy - but the strange noise is still there - abnd this wierd pattern on the rotors - both the same! - Any ideas? Will it all 'ride up with wear Sir!' Or are they goosed? Very pretty - but I don't think it should be like this...
I wrote to the manufacturer and got a helpful reply... Thanks for your enquiry. No, the surface should not look like this. It should be smooth. What you have is the result of 'chatter' or a resonance which occurs when metal is machined and there is a vibration of the cutting tips on the surface of the disc. With the machine this problem is avoided by using the 'silencer'. Every machine we supply includes 2 of these silencers as standard and the garage who did the job for you should have used their silencer. It takes 2 seconds to fit while machining. Using the silencer is a key part of the training we provide with every machine we supply. We have a permanent stock of spare silencers. If they have used the ... machine correctly (which again we train garages to do, and it's an easy skill to master) then your brake vibration will be eliminated. Your discs will eventually wear flat and the whirring noise will disappear but you shouldn't have to put up with that. Which garage machined your discs please? Best regards, The noise from the discs is getting less - and I have not been able to induce any judder from them so far
Not much point taking them back - not noticed any judder so far and the 'ripples are fading away - so no wories on my part
I'd be worried that the score marks may have given the disk a potential fracture line - but hey ho, the're only brakes
LOL 'Score marks' - it's fretting - and I promise you I am continuing to polish them out just a little more every day I'm starting to miss the firework launching sound when I brake now...
I can never understand why people skimp and scrape when it comes to brakes but hey ho, it's not my car. Just hope you don't end up in a brick wall or cause damage to the car through the judder
It's not scrimping and scraping mate... it's a semsible way of making a heavy costly part fit for service again... Also I wasn't sure that it was the brake discs since I hadn't had any judder until the track day... and when it started my son hadn't been driving particularly hard. When they started the cut it did seem as though there were some deposits on the disc that needed skimming off - not warping - a common myth, see here for some useful brake info from an expert... http://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths In the US a lot of brake services are accompanied by a 'free' brake disc skim - and in the UK the major customers are cars like Porsche and Ferrari see http://www.thesupercarrooms.co.uk/porsche-brake-disc-skimming-repair Probably the main reason it isn't common here is that it is not cheap - it took about an hour to do and cost £60 for both discs. Most cars if you weren't bothered about having the best brakes you could just buy OE replacement discs for less than that... - if they had used the silencer (see my previous post) it would have been smooth... As it is it has taken a couple of weeks to polish out... But no more judder (so far LOL ) TBH Kev I can't understand people who spend thousands and thousands on a car to get it up to an awesome spec - and then get bored and flog it and buy something else and do it all over again... but we're all different I guess?