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striken2o
23-06-2009, 07:03 PM
Hi,

just wanted you opinions on whether to bed new brake pads then machine the rotors or machine the rotors then bed the pads or don't bother with machining the disks ?
ghz28
23-06-2009, 07:59 PM
Definitely machine the rotors then bed in new pads, no sense matching new pads to worn rotors.

Garry
Brockfan05
24-06-2009, 10:24 AM
Exactly what Garry said. And make sure you dont go undersize if you get them machined as they wont dissipate heat and will warp very quickly.
ShylanMotorsport
24-06-2009, 10:53 AM
I really do not like machining rotors.
And even good wuality rotors are not that expensive so I believe that replacement is the best option!
Dan_
24-06-2009, 02:06 PM
I really do not like machining rotors.
And even good wuality rotors are not that expensive so I believe that replacement is the best option!

Agreed. Even for my BM replacement rotors were only $50 ea
.charged.
24-06-2009, 03:22 PM
I only machine rotors when the runout is over 5 thou, if they are are more than that, get them skimmed. We have found on our car that even new rotors may have some runout causes pad knockoff, we usually check with a dial indicator and get them skimmed on the car and try and get under a 1 thou runout.
ShylanMotorsport
24-06-2009, 03:42 PM
I only machine rotors when the runout is over 5 thou, if they are are more than that, get them skimmed. We have found on our car that even new rotors may have some runout causes pad knockoff, we usually check with a dial indicator and get them skimmed on the car and try and get under a 1 thou runout.


Thats why i always have a little safety tap just to make sure i keep :driving:
instead of landing in a :shitstorm:
.charged.
24-06-2009, 10:11 PM
Thats why i always have a little safety tap just to make sure i keep :driving:
instead of landing in a :shitstorm:


saftey tap FTW mate :)
striken2o
24-06-2009, 10:16 PM
well i've had new pads fitted today and will get them machined soon
ShylanMotorsport
25-06-2009, 08:37 AM
saftey tap FTW mate :)

excuse my ignorance but what is FTW?
WOMBIE
25-06-2009, 08:47 AM
excuse my ignorance but what is FTW?

For The Win :hero:
ShylanMotorsport
25-06-2009, 11:05 AM
oh lol......thanks Wombie!
Duffman
25-06-2009, 11:35 AM
I really do not like machining rotors.
And even good wuality rotors are not that expensive so I believe that replacement is the best option!

Agreed. Even for my BM replacement rotors were only $50 ea

I'm guessing neither of you have had to price replacement 350mm AP or even aftermarket DBA rotors. A little more than $50 a pop! :yike:

That said, I'm not one to winge about the price when the time comes to replace them. Premium price for premium performance. However if they've still got plenty of life left in them, it doesn't make sense to throw them away when they can be machined and re-used, does it?
ShylanMotorsport
25-06-2009, 02:36 PM
The problem is machining the rotors makes them weaker.
I know you are going to say "but if they are still above min thickness it shouldnt make a difference" but i still preffer to spring for the extra.....
I dont think machining can ever get it right....if it is skimming to get rid of a lip then maybe......but not machining to remove a warp.
Especially on a performance package why would you even think about comprimising the performance?
Just my opinion.....
Duffman
25-06-2009, 04:08 PM
Skimming and machining are pretty much the same thing aren't they?
choppo
25-06-2009, 08:26 PM
Here is one to throw in the mix. I heard never ever get new pads and new rotors at the same time :dunno:
I didn't listen and did that and it was a disaster - could be coincidence?
Dan_
25-06-2009, 08:32 PM
Here is one to throw in the mix. I heard never ever get new pads and new rotors at the same time :dunno:
I didn't listen and did that and it was a disaster - could be coincidence?

Really? I did it with the BM and had no issues. I wasnt running ABS though :hide:
choppo
25-06-2009, 08:45 PM
I wasnt running ABS though :hide::rocket: What was that 'Helium Man'? Dont worry, im going that direction right now :wave: Not for EC, but the next round... hmmm
See what happens guys when you put on a Pit Chief Head Honcho (PCHH)... they bash you around the ears all the time :swear:. Also, now ive got him talking in my ear as i go round and round and round, then off ;)
ShylanMotorsport
25-06-2009, 08:53 PM
Skimming and machining are pretty much the same thing aren't they?

Kinda. I believe a skim is taking the high points off.....that is what i was taught....
A machine is completly removing a layer so to speak......
Maybe my TAFE teacher was on drugs????:keen: :woohoo: :drinking:
This could also be very true! :lol:
ShylanMotorsport
25-06-2009, 08:56 PM
:rocket: What was that 'Helium Man'? Dont worry, im going that direction right now :wave: Not for EC, but the next round... hmmm
See what happens guys when you put on a Pit Chief Head Honcho (PCHH)... they bash you around the ears all the time :swear:. Also, now ive got him talking in my ear as i go round and round and round, then off ;)


My crew is in my ear all the time on the track too!
It is so friggin frustrating the sound of my own voice.....
it makes me drool with the way my helmet pushes my cheeks together......
Yelling at yourself and other drivers in a helmet is not always a good thing! :lol:
choppo
25-06-2009, 09:00 PM
Kinda. I believe a skim is taking the high points off.....that is what i was taught....
A machine is completly removing a layer so to speak......
Maybe my TAFE teacher was on drugs????:keen: :woohoo: :drinking:
This could also be very true! :lol:
BTW, again i didn't believe until i saw it... 'skimming' unfortunatley leaves (in most cases) a high spot every time. The lathe tool 'skips' over the hard spots. You can see them on the rotor. The only way to get them flat is by surface grinding them, which is way different than the average skim or similar on effectively a lathe in the back of a van/ or on the car. Great for a quick fix though, but not a long term solution
ShylanMotorsport
25-06-2009, 09:16 PM
BTW, again i didn't believe until i saw it... 'skimming' unfortunatley leaves (in most cases) a high spot every time. The lathe tool 'skips' over the hard spots. You can see them on the rotor. The only way to get them flat is by surface grinding them, which is way different than the average skim or similar on effectively a lathe in the back of a van/ or on the car. Great for a quick fix though, but not a long term solution

Chop....again you are pointing out the reasons why i do not like and do not agree with machining rotors.........