Free 186 More Best Homemade Tools eBook:  
Get 2,000+ tool plans, full site access, and more.

User Tag List

Results 1 to 4 of 4

Thread: Portable disc brake rotor lathe - GIF

  1. #1
    Jon
    Jon is offline Jon has agreed the Seller's Terms of Service
    Administrator
    Supporting Member
    Jon's Avatar
    Join Date
    Jan 2012
    Location
    Colorado, USA
    Posts
    25,446
    Thanks
    7,925
    Thanked 38,616 Times in 11,283 Posts

    186 More Best Homemade Tools eBook

  2. #2
    Supporting Member
    Join Date
    Mar 2018
    Posts
    79
    Thanks
    17
    Thanked 11 Times in 10 Posts
    So, what’s the conventional wisdom regarding turning disc brake rotors to relieve warpage? My dad suggested, decades ago, that turning would remove mass and weaken the structure.

    Are contemporary approaches better in that respect?

    2000 Tool Plans

  3. #3
    Supporting Member hemmjo's Avatar
    Join Date
    Feb 2017
    Posts
    2,541
    Thanks
    224
    Thanked 1,446 Times in 820 Posts

    hemmjo's Tools
    If your rotors are warped, you have to either turn them, or replace them. If you turn them it trues the surface. The turning of a warped rotor actually make it more likely to warp again. As you mentioned will be thinner than before, which leads to more heat build up. BUT, it will also be of less consistant thickness since you had to cut more off of some spots, and less off of other spots in order to make surface flat.

    There are many things that cause rotors to warp. Before you do anything, read this;

    https://www.crossdrilledrotors.ca/bl...-rotor-warping

    Your dad was correct.

  4. #4
    Supporting Member NeiljohnUK's Avatar
    Join Date
    Dec 2017
    Posts
    614
    Thanks
    59
    Thanked 229 Times in 162 Posts

    NeiljohnUK's Tools
    Quote Originally Posted by hemmjo View Post

    There are many things that cause rotors to warp. Before you do anything, read this;

    https://www.crossdrilledrotors.ca/bl...-rotor-warping
    Interesting, though not entirely accurate, cross-drilling and slotting may assist with cooling, but the main reason for doing such things is to vent the gases evolving from the brake friction material resins that actually grip (brake) the rotor, trapped gases are major cause of fade, slotted pads help too. My father was the Ferodo tech who developed the first slotted pads for a Jag D type racer in Southampton, using two hacksaw blades side-by-side in a standard hacksaw frame, initially for multiple leading edges to clear water as wet discs didn't work as well as drums, then in dry races the racer reported less fade with the 'wet' slotted pads. Having been better braked than the factory D types Ferodo sent an engineer to question what they were doing, soon after slotting pads became a manufacturing process.



    186 More Best Homemade Tools eBook

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •