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Old 06-16-2009, 08:23 PM   #1
jlaird
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opening holes in rotors

I need to ever-so-slightly open the holes up in my rotors, probably around a 1/32". Is this something I can safely do myself with a drill press or should I take the rotors to a machine shop?

-josh
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Old 06-16-2009, 10:36 PM   #2
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Re: opening holes in rotors

What holes are you refering to? Are they cross drilled rotors? If you do open them up, you will need to clean the chamfer again.

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Old 06-17-2009, 06:27 AM   #3
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Re: opening holes in rotors

nothing to do with cross drilled rotors. I'm talking about the holes for the studs. Its a 5x5 pattern. I had my axles redrilled by moser and the studs are slightly off alignment...or the holes in the rotors are slightly small.
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Old 06-17-2009, 07:38 AM   #4
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Re: opening holes in rotors

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Originally Posted by jlaird View Post
nothing to do with cross drilled rotors. I'm talking about the holes for the studs. Its a 5x5 pattern. I had my axles redrilled by moser and the studs are slightly off alignment...or the holes in the rotors are slightly small.
Moser probably put slightly larger studs in than factory
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Old 06-17-2009, 11:12 AM   #5
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Re: opening holes in rotors

jlaird,... if you have a drill bit that fits the exact size of the existing hole,... you can locate it with that drill bit, lock/clamp the rotor in place, and then switch to the bigger size drill bit and the enlarge the hole. Then you will have to repeat this step until you have them all drilled. Not as easy as using a mill,... but you can get the job done. You just need to verify that you are in the "center" of the existing hole before you try to make it bigger.
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Old 06-17-2009, 02:01 PM   #6
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Re: opening holes in rotors

Quote:
Originally Posted by jlaird View Post
I need to ever-so-slightly open the holes up in my rotors, probably around a 1/32". Is this something I can safely do myself with a drill press or should I take the rotors to a machine shop?
I vote machine shop. You're as handy as they get, but they'll have the equipment and they'll have the responsibility.
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Old 06-17-2009, 06:02 PM   #7
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Re: opening holes in rotors

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Originally Posted by lolife99 View Post
jlaird,... if you have a drill bit that fits the exact size of the existing hole,... you can locate it with that drill bit, lock/clamp the rotor in place, and then switch to the bigger size drill bit and the enlarge the hole. Then you will have to repeat this step until you have them all drilled. Not as easy as using a mill,... but you can get the job done. You just need to verify that you are in the "center" of the existing hole before you try to make it bigger.
this is the exact way I was intending on doing it.

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I vote machine shop. You're as handy as they get, but they'll have the equipment and they'll have the responsibility.
You have a point too. Also my crappy craftsman drill press has a little play in the chuck, so I'm concerned about the bit walking or ovaling out the hole. I have a buddy coming over tonight to look at it. He can do it on a mill for me.
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Old 06-17-2009, 08:08 PM   #8
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Re: opening holes in rotors

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Also my crappy craftsman drill press has a little play in the chuck
We must have the same model
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