XPost: comp.mobile.android, misc.phone.mobile.iphone   
   From: xenolith@optusnet.com.au   
      
   On 12/5/2022 10:33 am, Andy Burnelli wrote:   
   > sms wrote:   
   >   
   >> "Back in the olden days" I kept a spare set of rotors so when I was   
   >> doing a brake job I didn't have to stop and take the rotors to be   
   >> machined in the middle of the work. I'd then take the rotors that I   
   >> removed to be put on a lathe (for free since my relative had a repair   
   >> shop) and they'd be ready for the next brake job in 25,000 miles or so.   
   >>   
   >> But back then discs were thick and heavy and could be machined   
   >> multiple times before they were too thin. Nowadays rotors are so thin   
   >> they can usually not be machined even once, but they've also become   
   >> less expensive (when adjusted for inflation).   
   >   
   > I wonder if _anyone_ here realizes _why_ there's a minimum thickness spec?   
   >   
   > HINT: It's not what everyone intuits (e.g., it's not for heat dissipation).   
      
   It is actually so the rotor can *hold more heat*. It's all about   
   *heating capacity*, not to cooling. You gain SFA extra surface   
   dissipation area when you increase the disc thickness. With a thin   
   (below spec) rotor, you reach brake fade temperatures much more quickly   
   - it's related to the above point. Also, the thinner the disc, the   
   greater the likelihood of warping related to strength and heat holding   
   capacity..   
      
      
      
   --   
   Xeno   
      
      
   Nothing astonishes Noddy so much as common sense and plain dealing.   
          (with apologies to Ralph Waldo Emerson)   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)