is on car rotor cutting the best method?

[ToadU]

Originally Posted by Mainia
Up in the upper Midwest rust belt, rotor cutting is so 1980s, you just get new rotors. Since cutting them cost almost as much as new ones.


This ^^^^

And only if needed. Honestly, if there is no pulsation in the peddle or steering wheel and the rotors measure still safe 90 plus percent of the time we just replace the pads. I'm not a fan of turning rotors because it makes them thinner and thus more likely to warp. If the vehicle drives right just slap pads on it and be done. Truly simple and almost always fine.

 

[HangFire]

Originally Posted by Cujet
It's good to know that if a rotor warps when hot, it's going to warp when hot after it's been turned.

One thought is that the recycled metals are distributed unevenly in the disk. Another is uneven cooling, the metals in one location were "tempered" by a red-hot stop, then keeping the pads clamped on that location while the rest of the rotor slowly cools.

Regardless of why it happens, "IF" you experience heat related warping, replace the rotor.


I would add, after confirming that the rotors truly are warped.

 

[HangFire]

The gradual elimination of copper in pads is increasing the number of rotors diagnosed as warped, as there is less metal scraping off excess deposits that cause shudder.

I never had a problem with my aftermarket rotors on the Pilot, but the previous owner had the factory rotors turned on-vehicle by the Honda dealer after the first pad slap (by same dealer), all before I bought it. Those rotors lasted the normal life of the pads before I put on the aftermarket rotors and pads. So that is one anecdote towards the effectiveness of Honda's on-vehicle rotor turning.

 

[The Critic]

Originally Posted by HangFire
The gradual elimination of copper in pads is increasing the number of rotors diagnosed as warped, as there is less metal scraping off excess deposits that cause shudder.

I never had a problem with my aftermarket rotors on the Pilot, but the previous owner had the factory rotors turned on-vehicle by the Honda dealer after the first pad slap (by same dealer), all before I bought it. Those rotors lasted the normal life of the pads before I put on the aftermarket rotors and pads. So that is one anecdote towards the effectiveness of Honda's on-vehicle rotor turning.

According to my sources, the copper got replaced with steel.

 

[The Critic]

Originally Posted by Cujet
It's good to know that if a rotor warps when hot, it's going to warp when hot after it's been turned.

One thought is that the recycled metals are distributed unevenly in the disk. Another is uneven cooling, the metals in one location were "tempered" by a red-hot stop, then keeping the pads clamped on that location while the rest of the rotor slowly cools.

Regardless of why it happens, "IF" you experience heat related warping, replace the rotor.

Not saying I agree or disagree, but this is one OEM's position:

"American Honda does not allow replacement of brake
discs under warranty unless the brake disc is beyond
its service limit for refinishing. If the brake disc is within
its service limit, you must refinish it. Maximum
refinishing limits may be found in the Conventional
Brakes section of the appropriate electronic service
manual.
Refinish brake discs only when they are scored or out
of specification for runout or parallelism. See the
appropriate electronic service manual for the
specifications.
American Honda requires refinishing of the front brake
discs with an on-car brake lathe that mounts to the
steering knuckle or hub using specially designed
Honda/Acura specific adapters. It is critical to use an
on-car steering knuckle-mounted lathe because it
corrects the hub and disc runout as an assembly. Even
a very small amount of runout, which may not be felt
initially, will grow and will be felt as brake pulsation as
the discs are subjected to heat and wear over time and
mileage."

https://www.procutusa.com/pdf/oem/2014-Pro-Cut-American-Honda-Service-Bulletin-00-088.pdf

 

[joel95ex]

my accord had captive rotors so i swapped the acura hubs and rotors (ROH conversion ) and never looked back.