Have you ever heard of turning the rotors while they are still on the car?

[Chrome_thangs]

The place where i got my alignment does it. They said it's better than taking em off to do it. How true is this?

[YK86]

I'm not a proffesional but I have never heard of doing it with it still on the car.

[anchovies]

They have it in some bigger shops.
They call it "on-car rotor turning" brake lathe.
Saw it on auto-week or two-guys garage or something. Don't know if it's better than conventional way.

[AZmike]

They say it's ok in the Honda service manual.

[dj99]

On the newer Accords (and others), the rotors don't pop off with two screws like ours do. ;) You have to take the whole hub off to get the rotor too. So it's just easier and quicker to lathe them right on the car. They roll this beast up to the car on the hoist and bolt it to the hub.

[89NinjaAccordLX]

Ford and Honda both use the on-car system now. Other manufacturers might as well, but my school taught us how to use the two from Ford and Honda. On-car is better than off car for this reason: on-car takes hub runout and other factors on the car into account when cutting the rotors. The ford machine turns the rotor wheras the Honda machine uses the engine power to turn the axles and thus cut the rotors. However, the first time you ever USE one of the on-car lathes you will be frustrated as crap. There's so many adjustments and calculations you have to make just to set up the lathe right its insane. Speed comes with practice though. You might just want to take off the rotor and say "screw runout". Whatever.

[Chrome_thangs]

On-car is better than off car for this reason: on-car takes hub runout and other factors on the car into account when cutting the rotors.
Ya that what he was telling me. I thought it was bullshit because i'd never heard about it. Thnx

[AccordEpicenter]

yeah its pretty neet, ive seen it done. Its way faster and the finished product is just as good if not better. BTW you cant turn the rotors on the back wheels (or a non-engine driven wheel) because the car is running and in gear to turn the rotor on the car to resurface.

[surenoracer13]

the reason they say its better is so they dont have to take the time to take the rotor off then put it back on cuz they are working on a flat rate. but sometimes its better to take off the rotor to turn it cuz if u bent the axel on a corner or something ur making the rotor true to the axel. so if u take it off and turn them and test drive it and u feel the wobbel from run out still that means theres a problem with something else in ur brakes/suspension assembly, so sometimes juss to take it off the rotor and turn it helps find other problems.and sometimes it helps cover ur ass cuz if the customer comes back and complains bout the same problem u have to do it again for free so sometimes its better to take the extra time and do it the long way

[Chrome_thangs]

Originally posted by AccordEpicenter
yeah its pretty neet, ive seen it done. Its way faster and the finished product is just as good if not better. BTW you cant turn the rotors on the back wheels (or a non-engine driven wheel) because the car is running and in gear to turn the rotor on the car to resurface.
Hmmm...no, i saw them doing a big ass farm trucks front rotors and i pretty sure they are rear wheel drive. Plus no one was in the car pushing the pedal

[89NinjaAccordLX]

Like I said... the Rotunda on-car brake lathe that ford uses is self powered and doesn't need the engine power.

[AccordEpicenter]

I saw a snap on one for cars... That one uses the cars power to tun the rotor