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Old 09-06-11, 12:25 PM   #1
gearbasher
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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?
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Old 09-06-11, 01:03 PM   #2
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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.
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Old 09-06-11, 01:57 PM   #3
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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.
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Old 09-06-11, 02:14 PM   #4
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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.
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Old 09-06-11, 02:59 PM   #5
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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.
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Old 09-06-11, 03:48 PM   #6
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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.
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