The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > General Truck Forums > Suspension

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 06-16-2009, 08:23 PM   #1
jlaird
Senior Member
 
jlaird's Avatar
 
Join Date: May 2004
Location: johnstown, NY
Posts: 2,393
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
jlaird is offline   Reply With Quote
Old 06-16-2009, 10:36 PM   #2
N2TRUX
Happy to be here
 
N2TRUX's Avatar
 
Join Date: Mar 2000
Location: Cypress, TX
Posts: 39,021
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.

That bevel is critical in preventing stress cracks as well as chatter on the brake lathe if you have to turn them.
__________________
Follow me on Facebook and Instagram @N2trux.com

Articles-

"Jake" the 84 to 74 crewcab

"Elwood" the77_Remix

85 GMC Sierra "Scarlett"

"Refining Sierra"
N2TRUX is offline   Reply With Quote
Old 06-17-2009, 06:27 AM   #3
jlaird
Senior Member
 
jlaird's Avatar
 
Join Date: May 2004
Location: johnstown, NY
Posts: 2,393
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.
jlaird is offline   Reply With Quote
Old 06-17-2009, 07:38 AM   #4
ghettoluxury
Registered User
 
ghettoluxury's Avatar
 
Join Date: Apr 2009
Location: Waynesfield Ohio
Posts: 1,991
Re: opening holes in rotors

Quote:
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
__________________

1949 Five Window, 1973 Step Side, 2000 Z71
ghettoluxury is offline   Reply With Quote
Old 06-17-2009, 11:12 AM   #5
lolife99
67-72 parts collector,…
 
lolife99's Avatar
 
Join Date: Nov 2002
Location: Mid-MO
Posts: 22,700
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.
__________________
Keith

Convert to disc brakes.
http://67-72chevytrucks.com/vboard/s...d.php?t=444823
lolife99 is offline   Reply With Quote
Old 06-17-2009, 02:01 PM   #6
XXL
Señor Member
 
XXL's Avatar
 
Join Date: May 2002
Location: Edge of the world
Posts: 5,367
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.
XXL is offline   Reply With Quote
Old 06-17-2009, 06:02 PM   #7
jlaird
Senior Member
 
jlaird's Avatar
 
Join Date: May 2004
Location: johnstown, NY
Posts: 2,393
Re: opening holes in rotors

Quote:
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.

Quote:
Originally Posted by XXL View Post
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.
jlaird is offline   Reply With Quote
Old 06-17-2009, 08:08 PM   #8
XXL
Señor Member
 
XXL's Avatar
 
Join Date: May 2002
Location: Edge of the world
Posts: 5,367
Re: opening holes in rotors

Quote:
Originally Posted by jlaird View Post
Also my crappy craftsman drill press has a little play in the chuck
We must have the same model
XXL is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 03:32 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com