Advertise on Bikeforums.net



User Tag List

Results 1 to 6 of 6
  1. #1
    Senior Member gearbasher's Avatar
    Join Date
    May 2009
    Location
    Sitting on my butt in front of a computer
    Posts
    334
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Crown race cutting question.

    I'm in the process of a complete overhaul on my '98 Guerciotti. When I bought the frame, back in 98/99, I was told it was completely preped. Well, I noticed the fork crown race on my Record headset was cracked. Over the years I've purchased many frame tools and now I do all my prep work. I checked the crown race seat with a Campy go/no go guage and it needs cutting. My question is: The seat is chromed and I do not want to destroy my nice VAR cutter on the chrome, so how do I remove the chrome? I read that it should be filed off. If this is right, how do I not go too far with the file?
    Thanks
    "Trying is the first step towards failure." --- Homer Simpson

  2. #2
    Senior Member
    Join Date
    Sep 2010
    Posts
    2,833
    Mentioned
    4 Post(s)
    Tagged
    0 Thread(s)
    gearbasher: I am not certain what exactly you are cutting, ID or depth, but I would ask a competent machine shop to grind it or to mill it with a carbide cutter.

  3. #3
    Senior Member
    Join Date
    Feb 2005
    Location
    Oklahoma
    My Bikes
    Trek 5500, Colnago C-50
    Posts
    9,174
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    There is a special tool for "facing" the crown race. Find an LBS that has the tool and have them do it. I don't know if there are any special problems with facing chrome.

  4. #4
    slow as I ever was Ex Pres's Avatar
    Join Date
    Dec 2007
    Location
    an imposter living in the 35223
    Posts
    5,746
    Mentioned
    5 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Al1943 View Post
    There is a special tool for "facing" the crown race. Find an LBS that has the tool and have them do it. I don't know if there are any special problems with facing chrome.
    There is a problem cutting chrome (tool wear), which is why the OP doesn't want to attack it. But if your LBS will, I'd let them have at it. But they'll probably pass as well, unless all they know is carbon .

    As far as filing, I'd just be careful. Take a couple swipes, take a look. If you can use tools, you can be an adequate judge of this process. The cutter will round out any "corners" you leave.
    72 special CNC ______ 72 Frejus (ala Legnano) _73 Holdsworth Record
    80 Ranson__________ 80 unknown French____ 83 Trek 600 (620 styled)
    85 Gianni Motta_____ 90 Miele Gara ________ 02 Casati Dardo #1
    02 Casati Dardo #2 __ 03 Casati Dardo ______ 08 BF IRO (fixed/SS)
    09 Dogma FPX magn_ 10 Vassago Fisticuff (IGH)

    For Sale: _________ 78 Raleigh Professional __ 82 Peugeot PXN10
    85 Trek 560_______ 88 Guerciotti GLX

  5. #5
    Senior Member gearbasher's Avatar
    Join Date
    May 2009
    Location
    Sitting on my butt in front of a computer
    Posts
    334
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    To clarify: I need to cut the OD of the crown race seat on the fork. I have the proper tool and I've done the job a number of times. It's just that this is a fully chromed fork (crown race seat and all) and chrome destroys the cutter. I do not want to ruin an expensive cutter. I was hoping someone had a method to remove the chrome other than taking a file to it. I'm afraid of filing low spots on the seat.
    "Trying is the first step towards failure." --- Homer Simpson

  6. #6
    Senior Member
    Join Date
    Sep 2010
    Posts
    2,833
    Mentioned
    4 Post(s)
    Tagged
    0 Thread(s)
    gearbasher: Grinding is the way to go. A local automotive machine shop should have no problem grinding (and polishing, for that matter) the OD of the seat to close tolerances. Just bring the bearing to them to measure.

Posting Permissions

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