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Topic: Rotor resurface or replace

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Rotor resurface or replace (1/47)
 11/12/11 8:48pm
daveo76
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Vancouver, WA - USA

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1976 Silver/Firethorn. L48, 4spd. Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.


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I finally purchased a dial indicator and magnetic mount (Harbor Freight) and measured my runout on the fronts.  Looks to be about .009 or so on the outer edge.  Too much according to my Haynes manual (.005).  I also checked overall thickness with a set of calipers and I'm getting close to the 1.23" minimum.  Is it worth it or possible to have these turned?  If so, how do you find a good shop (no Bubba's) to do this without screwing them up?  But...I did some searching online and it looks like I can get a set of Delco fronts for about $35 apiece.  Seems like it would make more sense to just replace?  Thanks guys.

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1976 Silver/Firethorn.  L48, 4spd.  Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.
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Re: Rotor resurface or replace (2/47)
 11/12/11 8:57pm
crossfire1982
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If they are close to the minimum Id go ahead and get the Delcos.  Although they are Delco, dont assume you will not have runout.  You will still have to check runout and "clock" them and/or shim them to get minimum runout.

|UPDATED|11/12/2011 5:57:39 PM (AZT)|/UPDATED|
Re: Rotor resurface or replace (3/47)
 11/13/11 12:15am
Adams' AppleLifetime Member
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I agree. For the price, it's not worth having the old ones turned, only to find they are too thin, AND the guy that did them screwed them up....so you have to buy new ones anyway.
Be sure to CLEAN the new rotors in hot soapy water, with a good stiff brush, and then blow dry them. This will get all of the metallic particles off of them, and make it easier for the pads to bed in.


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Re: Rotor resurface or replace (4/47)
 11/13/11 3:00am
daveo76
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1976 Silver/Firethorn. L48, 4spd. Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.


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Thanks guys!  I'm going to order the Delcos.  A couple more questions, though: what's the method for drilling out the rivets on the originals (e.g. drill bit size, go from outside or inside, etc.?)  Assuming this is something you don't want to do with the hub mounted on the spindle?  

The runout thing has me concerned.  Is this tricky to get right?  Chip, I'm assuming by "clock" you mean rotating the rotor to different stud positions to try and minimize the runout?  And if you can't get it within spec then you need to shim.  It looks like there are tapered donut shims available that go over all the studs (spendy), but then there were also examples on the net in which guys just used hardware store shim material over one or more studs.  This is pretty complicated and my manual does not cover it - thanks again for the help.  


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1976 Silver/Firethorn.  L48, 4spd.  Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.
Re: Rotor resurface or replace (5/47)
 11/13/11 8:46am
yostusota
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Dave the shim thing really isn't that hard..use the dial indicator to find the low spot..mark the rotor at the low spot and put a shim under that spot on the wheel stud..I've used soda cans for this and it works fine..just cut a circle out of one and cut a hole in it so it goes around a wheel stud....this works to a point but it should get the run out down to where its in spec..if they end up needing fine tuned like I like them to be get them cut on the car with a pro cut machine..Google it..there's plenty of info out there on these things...the rivets are easy..drill bit size isn't that important..just go big..I think the last time I used a to 3/8 bit..cut the head off with that then used a punch to push the rest of the rivet out..don't try and drill all the way thru the rivet...its a 5 minute job no problem..and yes do it off the car on the front..kinda have to do them on the car on the rear..have fun!

|UPDATED|11/13/2011 5:46:00 AM (AZT)|/UPDATED|


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Re: Rotor resurface or replace (6/47)
 11/13/11 1:23pm
crossfire1982
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This really isn't that bad of a job and it certainly ain't rocket science.  The rivets can be drilled out on the car or you can remove the hub and use a drill press but it is a bit easier if you remove the hub.  Either way try to be accurate with your center punch and start with an undersized bit to drill through the center of the rivet then progress to a larger bit.  once you have progressed to the larger bit and the head of the rivet has been removed and only the barrel remains in the hole you can drive the rivet out with a punch and hammer. Even though the head of the rivet is gone the barrel is swedged against the hole in the rotor and may not want to come out willingly. Once you get the hub and rotor separated you can clean up the face of the rotor before putting the new one on. 

Yep, Ive seen the tapered rotor shims online too and they are really proud of them $$.  I used regular old .002 stainless steel shim stock form a local industrial supply on mine,  and cut the shims so they approximated the radius of the outer  and inner edge of the rotor and punched a hole in the appropriate place so that the shim would fit over the lug nut stud. If you cut the shims just right you can put them on neighboring studs without overlap if you need to or cut a double one if needed.

With the rotor mounted on the car you clock the rotor  to all 5 possible positions and see if you can get runout within spec and if not, then start with the shims.  I used a felt tipped  marker to mark the end of one studs when clocking and beside each of the holes Id write the runout when that particular hole was on the marked stud.  You will have to securely bolt the rotor to the hub each time you move to a different position, use at least 2 or 3lug nuts so your readings are accurate.  Get as much runout out as you can by clocking and then start with the shims.  Mark the rotor at its lowest point and use shims to bring it up.  You may have to put the shims on more than one stud and this gets a little tedious.  Once you get the shims right you can just leave it right there with the rotor itself holding everything together or you can get industrious and bolt the rotor to the hub, its your choice but bolting insures that everything is going to stay in place.  Ive attached a link from an old post with some pics that may be helpful. The link is not showing as clickable with the new forum software for some reason so you may have to copy and paste into your browser.  Sorry for the long post but you guys know I'm long winded.

https://www.c3vr.com/vrforums/brake-rotor-rivets_message387951.html 


(inserted clickable link-aapple)



|UPDATED|11/13/2011 10:23:27 AM (AZT)|/UPDATED|
Re: Rotor resurface or replace (7/47)
 11/13/11 1:29pm
corvette440hpLifetime Member
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Dave, I used colbalt bits to drill out the rivets. As was mentioned the rotors should just be replaced. The run out will need checking as was mentioned. It does take time and patience to dial everything in. The pop can shims work really well. I fortunately have a cannister of various size washers that are also different thicknesses. A guy that I knew worked at a place called Freeway Washer. He put together a major assortment of washers that were brass, steel, copper, and stainless. I find it very valuable at times. And always recheck with the rotor secured.....as was mentioned. I marked the studs with different color marking paint pens to know where I was. And you more than likely need to use more than one shim.     

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Re: Rotor resurface or replace (8/47)
 11/13/11 5:36pm
lukesvetteLifetime Member
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I drilled out my rivets with ease - soft stuff. The replaced with deco replacements and metallic pads. Bled the brakes and they're better than new.

As mentioned, rotors these days are cheap enough - the cost of turning them almost isn't worth it...

Just my 2Cts Wink

Good luck!!

Paul
Re: Rotor resurface or replace (9/47)
 11/13/11 9:20pm
daveo76
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Vancouver, WA - USA

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1976 Silver/Firethorn. L48, 4spd. Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.


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Thanks guys!  This is some great information and I appreciate hearing about all the tricks and procedures you all used.  I feel a lot better about this little project now.   I ordered the two Delco fronts last night from Amazon.  We recently bought an Amazon Prime membership - ended up getting free two day shipping on these cast iron beasts!  Can't beat that.  

Bad news is I'm only tackling the fronts for now.  Assuming I can get a hard pedal after I bleed I'm going to call it good and mess with the rears next winter -- too many other projects (and stuff to spend money on) this winter.  I had the rear wheel bearings replaced by a Corvette shop a few years back (very few miles on it since then) so I'm hoping I'm good.  

Thanks again!  


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1976 Silver/Firethorn.  L48, 4spd.  Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.
Re: Rotor resurface or replace (10/47)
 11/24/11 4:05am
daveo76
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Vancouver, WA - USA

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1976 Silver/Firethorn. L48, 4spd. Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.


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Well I took the day off today for some chores which included some time this afternoon/evening trying to shim those rotors.  After several hours I ended up getting both (front only) to about .003-.004 runout.  Does that sound pretty good, or should I keep trying?  I used brass shim sheet from the hardware store.  It has .001, .002, .003, and .005 sizes in 3"x4" sheets.  I still have the .001 left - I probably could add in a bit of that over one or two of the studs to try to get that last little bit, but I had to walk away for awhile....

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1976 Silver/Firethorn.  L48, 4spd.  Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.
Re: Rotor resurface or replace (11/47)
 11/24/11 8:26am
crossfire1982
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If you are at .003 - .004 runout Id say leave it alone.  Glad to see you got it doneClap
Re: Rotor resurface or replace (12/47)
 11/24/11 9:13am
yostusota
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Have you torqued the wheel on yet? If not do that on and off a couple of times to make sure everything is crushed into place..take one more measurement and see where you are..be carefull that you are not measuring any bearing play too..you're getting down to the really close stuff so anything can be a factor in a change in runnout..make sure all the lug nuts are torqued the same when you check the run out...like I said earlier..I like them as close to 0.000 as possible..just know any runnout you have now will get worse once you heat them up..I guess I'm assuming you are going to drive this car hard once its all done..the number you have is teter toter hand...if you have time get it to the lowest number..have fun!!

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Re: Rotor resurface or replace (13/47)
 11/24/11 12:59pm
daveo76
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Vancouver, WA - USA

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1976 Silver/Firethorn. L48, 4spd. Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.


Joined: 8/25/2005
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Thanks guys.  I'll torque the wheels on with all five lug nuts and then check again to see where I'm at.  Ready to be done with this one!

Happy Thanksgiving!


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1976 Silver/Firethorn.  L48, 4spd.  Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.
Re: Rotor resurface or replace (14/47)
 11/24/11 2:31pm
tb2k82ceLifetime Member
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Just for info I saw a test on the stopping power of turned rotors over new ones.  I thought I saved it but apparently not.  Anyway it demonstrated that the grooves from turned rotors (all most all turned rotors do some more course than others) can significantly reduce stopping power.  I do not remember exactly what it was but it was over 30%.  I'm thinking it was closer to 50% in some cases.  I think that would be way more than what a little run out would cause.

If anyone knows about that video it could be a good link to let everyone look at.  Basically if you have your rotors turned make sure it is a real fine slow turning.  The less grooving the better.  Then sand off the tops of the grooves.  If you do not what happens is the grooves move the disc (like a record needle on a record) when they meet the maximum they jump and restart the process over.  Turning the jump period you have not breaking power. 
Re: Rotor resurface or replace (15/47)
 11/24/11 2:59pm
yostusota
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I remember that one!! Don't remember where it was..yeah quality rotor machining is define a big problem..its only going to get worse..shops are cutting time on everything which makes guys work faster and care less about quality..don't machine them unless you have to..the run out is important for caliper seal issues but it may be just a trade off.

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Re: Rotor resurface or replace (16/47)
 11/25/11 1:42pm
tb2k82ceLifetime Member
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Yes I really wish I could find that video it was an eye openner.  The more I think about it the reduction in breaking power do to what is normal rotor machining process was over 50%. 
 
I know after I say it I just desided that I would purchase new rotors. Doing what you needed to do to give you quality machining would be as expensive as rotors. That is if you could get someone who new what you were talking about.  I did a YouTube search and could not comeup with anything do you remember how long ago that was?
Re: Rotor resurface or replace (17/47)
 11/25/11 1:56pm
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Most, if not all, NEW rotors are mill finished, not turned, so you start with a perfectly flat, parallel surface on both sides.
Using a lathe, whether stand alone, or on-car, will put small grooves in the surface, very similar to a record album. The slower the final cut is on the rotor, the finer the grooves are...if the final cut is fast, it leaves larger grooves, and makes the pads want to jump around a lot. Yes, the pads will want to follow the grooves when the brakes are applied...no doubt aboot that. That's why we always use a sanding disc to knock the grooves down while the rotor is still installed(& turning) on the lathe. This gives us a more uniform surface, so the pads won't have as much of a groove to try to follow.
I don't guess I've seen the video...might be interesting. I think the variables would need to be called out tho...how were the rotors turned, at what speed, etc. Besides, testing braking distances on freshly turned rotors, with new pads, is kinda misleading, anyway. Pads and rotors need to be burnished, or bedded in, before making any hard stops....that's just common knowledge.
Do ya'll have any idea who did the comparison video?


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Re: Rotor resurface or replace (18/47)
 11/25/11 3:45pm
corvette440hpLifetime Member
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http://www.youtube.com/watch?v=RHjLxR2IE-s&feature=related     Pro-Cut Lathe Operation Time Lapse - YouTube



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Re: Rotor resurface or replace (19/47)
 11/25/11 4:33pm
yostusota
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Yeah that's about it..its hard to see but it actually moves back and forth to double cut the rotor so it does a fast cut and a slow cut at one time but only removing the same amount of rotor material as doing a single cut..it does leave a clean finish as long as the bits are good..the people that made the comparison video made rotors and pads..can't remember the company name but that's where it came from..it was fairly old as it was talking about ABS as something new.

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Re: Rotor resurface or replace (20/47)
 11/25/11 9:59pm
corvette440hpLifetime Member
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This is a great place for lots of informatiom.........more than you can ever hope for:  

http://www.stoptech.com/technical-support/technical-white-papers



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Re: Rotor resurface or replace (21/47)
 11/25/11 10:01pm
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Now this is one that you need to see about the grooving of the rotors. It's what you were looking for..................

http://www.oeqf.com/techinfo/scratching/scratching_lg.htm



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Re: Rotor resurface or replace (22/47)
 11/26/11 3:43pm
tb2k82ceLifetime Member
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That is it.  How in the heck did you find it?? What did you use for a search?
When you think about all the times you turned your rotors it is kind of scary. To think the times I was broke and just replaced my pads I was much better off safety whys. 

|UPDATED|11/26/2011 12:43:14 PM (AZT)|/UPDATED|
Re: Rotor resurface or replace (23/47)
 11/26/11 6:55pm
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tb2k82ce said: That is it.  How in the heck did you find it?? What did you use for a search?
When you think about all the times you turned your rotors it is kind of scary. To think the times I was broke and just replaced my pads I was much better off safety whys. 


I knew what you were looking for..........I was waitingEvil Smile to see if anyone would come up with it. I guess I'm eboEvil Smile 2 ......(he taught me well).

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Re: Rotor resurface or replace (24/47)
 11/28/11 1:03am
daveo76
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That's an interesting video.  Will make me think twice about turning rotors next time, but it sounds like turning is still a viable option if all the conditions are met and the grooves are removed with non-directional finishing.  I'd be interested in finding out more about that procedure.  So is that the kind of thing where you bring them home from the shop and then apply that finish yourself with a hand-held random orbital sander?  Or should that be applied with a special machine while still in the lathe fixture?  I'd be worried about screwing them up worse than before.  I'm not asking for my 'Vette, but my wife's Honda Odyssey is starting to pulsate just a little and I was thinking I'd have the front rotors turned for starters.  

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Re: Rotor resurface or replace (25/47)
 11/28/11 9:14pm
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I would rather they did it where the rotors were resurfaced.........if they can and are willing to do it.

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Re: Rotor resurface or replace (26/47)
 11/28/11 9:56pm
yostusota
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Depending on the year Honda she has could really make a difference in cut or replace..the older ones had the hubs on the outside and had to press out the bearing to get the rotor off..I would highly suggest some kind of one the car brake lathe..I think its a tool Honda dealers have to have now since all the rotor issues they had..the finish should be done wherever the rotors are cut..

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Re: Rotor resurface or replace (27/47)
 11/28/11 11:20pm
daveo76
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Good to know, Rich!  About what year did they change, do you know?  We have an '07 - the generation started in '05, I think.  

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Re: Rotor resurface or replace (28/47)
 11/28/11 11:32pm
yostusota
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Yeah when I say old I guess I meant the first Gen..like 95!!.. the 07 is a simple set up..they had issues with the hub not being true so on the car became the norm in 01-02..don't get me started on the trans in that car!!!.In the video of the on car lathe it shows the guy using a wizzer wheel to burnish the surface and that works really good..I have access to the bodyshop sand paper cabinet so I use the 40 grit stuff that really works good for a finish..been using the on the car lathe now for at least 10 years and its worked great everytime.

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Re: Rotor resurface or replace (29/47)
 11/29/11 2:23pm
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Folks, there's no problem with having your rotors turned on a lathe, whether on-the-car, or on a bench lathe. They've been doing them like that for 100 years(drums & rotors). The main issue is operator skill, and lathe quality. I have an antique Accuturn lathe that will turn a rotor just fine. I do use a sanding disc in a die grinder, and knock the grooves down a bit, while the rotor is still turning on the lathe. Haven't had a problem yet. I have also re-done rotors that we had sent out to a machine shop, because they always seem to have too rough of a cut on them....they get in a hurry, so the final results suffers. That's the operator skills part...not a reflection of having them cut on a lathe...
Don't be askeered to have your rotors turned. If they are within the minimum thickness allowance, as marked on the rotor, turning them is fine. You just need to find a shop that is qualified to do it. Thumbs Up


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Re: Rotor resurface or replace (30/47)
 1/11/12 2:17pm
yostusota
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York, PA - USA

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1969 daytona conv. all original 350 350 380 4 sp w/air..and hard top


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Not to beat a dead horse but here's a rotor I did today on the car..


http://i1216.photobucket.com/albums/dd378/rweaver11/2011-12-02_15-27-32_808.jpg



(large image changed to link-aapple)


|UPDATED|1/11/2012 11:17:03 AM (AZT)|/UPDATED|


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Re: Rotor resurface or replace (31/47)
 1/8/12 1:52am
daveo76
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Vancouver, WA - USA

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I was talking to a the owner of a 'Vette resto shop today and he told me the front rotors DO need to be re-riveted on to the hubs.  Even after I told him the Delcos I purchased don't have the rivet holes he suggested I drill them.  I'm wondering if this is the case of him wanting to do the work, because I can't really see a functional need for re-riveting.  I know it'd be important for NCRS stuff, but that's not applicable in my case.  If my new rotors had the holes I'm sure I'd have them re-riveted or tap them for countersunk bolts, but I don't plan on drilling any holes.  Just looking for confirmation here to ease my mind.   Thanks, Dave

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1976 Silver/Firethorn.  L48, 4spd.  Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.
Re: Rotor resurface or replace (32/47)
 1/8/12 3:26am
yostusota
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If I remember right the reason they were riveted on was to have the hub and rotor trued before assembly..make things go faster on the line..plus the next yahoo to work on the car wouldn't take the rotor off and then have brake issues..like caliper or vibration..I think the answer is right there anyhow...you can buy the rivets from many company's...but those same ones sell rotors without the rivets..if there was a true safety issue would anyone be selling rotors without the holes to rivet them back on? I put the NAPA ones on the back if mine..they didn't have holes either.

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Re: Rotor resurface or replace (33/47)
 1/8/12 11:16am
rod7515Lifetime Member
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Red Lion, PA - USA

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I believe the choice to have rivets is with the person that owns the car. In my honest opinion they are not a functional part. As for removing the rotors from the hub I would agree with marking the rotor so they go back on at the same position but once the tire is bolted fast to the hub the rotor is in place just as the rivets would have held them from new. I actually resurface my rotors with an old brake lathe but I bolt them tight to the hub for turning. I make sure that when I put them on the car they go back in the same indexing location as when I turned them. I have not had any issues with mine at all and thats the way they would have been done before there was the new equipment to turn them while they stayed on the car. Dont get me wrong, I am sure that the new equipment today will probably do a better job then an old brake lathe, but if the cutting bits are new and the machine is in good condition a true rotor is a true rotor!
Rodney

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Re: Rotor resurface or replace (34/47)
 1/8/12 12:37pm
Adams' AppleLifetime Member
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Rotors do NOT have to be riveted to the hubs...period. As far as NCRS, we don't check crap like that anyway, except on Bowtie award cars.

The main reason for them being riveted to start with was, as Rich said, to make sure they were as true as possible, and to make assembly quicker on the line. It was not then, nor is it now, a safety issue. Personally, I prefer to keep the front rotors/hubs together as an assembly...something that is not possible with the rears on our cars. I don;t see the need to drill the rivets out on the fronts. If the rotors are too thin, or damaged to be turned, I'd just as soon replace the rotor/hub assembly as to drill the rivets, and just replace the rotor. That's just my personal thing. The complete hub/rotor assy isn't that much more expensive, imho, than going thru the hassle of drilling the rivets.

As far as re-riveting new rotors back onto a hub, that takes some serious hydraulic pressure/equipment to do correctly...not something most shops will have access to. Get one rivet mashed, with the rotor not fully seated to the hub, and you've got a problem that will never go away.

Thass my story, an I be stickin wid it....Geek


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Re: Rotor resurface or replace (35/47)
 1/9/12 2:18am
daveo76
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Vancouver, WA - USA

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1976 Silver/Firethorn. L48, 4spd. Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.


Joined: 8/25/2005
Posts: 857

Thanks for putting my mind at ease on this, guys.  I'm going to keep them un-riveted/un-bolted for sure.  I've read a lot about this lately and it seems like it was needed to true the hub/rotor as an assembly because the hubs were cast so poorly that there was no way they'd be in spec for runout if the rotors were just slid over the studs like on cars today.  Probably explains why I'm still having runout trouble on one of my new rotors.  I've tried many different combinations of shims around various studs and seem to be chasing my tail.  I'm considering going with one of those tapered shims that slides over the studs.  Rock Auto sells them for cheaper than I was expecting ($14 or so) and they make them for corrections of .003, .006, and .009.  Anyone have any experience with these?  




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1976 Silver/Firethorn.  L48, 4spd.  Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.
Re: Rotor resurface or replace (36/47)
 1/9/12 2:37pm
rod7515Lifetime Member
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Dave,
Another option would be to remove the hubs and have the rotors turned on the hubs then install them to the car. You shouldn't have to take more then a few thousandths to have them trued. Just a thought.
Rodney


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Re: Rotor resurface or replace (37/47)
 1/11/12 1:10am
daveo76
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Vancouver, WA - USA

Vette(s):
1976 Silver/Firethorn. L48, 4spd. Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.


Joined: 8/25/2005
Posts: 857

Thanks, Rodney.  Yeah, that could be an option to consider.  I'm assuming I'd just bolt the rotor to the hub with all the lug nuts (torqued properly and equally of course)?  I'm a bit ignorant about brake lathes, though - how would the assembly be attached to the lathe?  Do they attach through the hole for the spindle?  

I could also put everything together and once I get this car on the road I could drive it to a shop that has one of those on-car Pro Cut machines that I think Rich has mentioned.  

I'm really close on one side (.003) but on the other I think about the closest I've come is .007.  


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1976 Silver/Firethorn.  L48, 4spd.  Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.
Re: Rotor resurface or replace (38/47)
 1/11/12 10:24am
yostusota
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York, PA - USA

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1969 daytona conv. all original 350 350 380 4 sp w/air..and hard top


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Look at it as how much your time is worth..most shops charge 100$ to cut the rotors with the pro cut..just make sure your bearings are seated and adjusted properly..it will cut them if they are a little loose but not to loose..it will take out the bearing play with its automatic adjusting head..but it gets confused if its to loose..if they are not corvette guys pick up some piston holders for the calipers..it will keep them from coming out when the caliper is removed to cut the rotor on the car..they are found in the brake section of pretty much any catalog I've seen..I think they are under the 20$ for a set..if you have those it will take out the difficult corvette factor and then anyone can do it.. But like I said..how much is your time worth..plus the pro cut will only need to kiss the rotor to true it up and your done..if you do get that done make sure you specify that they only take off a minute amount of material..be need to go crazy on new rotors to kick that small amount of rotor run out off.. Your choice on this...you know what I have done..but then again..I got the machine..road trip??

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Re: Rotor resurface or replace (39/47)
 1/12/12 3:11am
daveo76
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Vancouver, WA - USA

Vette(s):
1976 Silver/Firethorn. L48, 4spd. Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.


Joined: 8/25/2005
Posts: 857

Yep, Rich, it sounds like that choice may not be too cost effective. Probably my best bet is to just keep messing around with shims. (I just need to get out there and work on it - haven't been out in the garage since before Christmas) Road trip, hmmm.... The distance between PA and Vancouver, WA may eat up that $100 pretty quick!

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1976 Silver/Firethorn.  L48, 4spd.  Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.
Re: Rotor resurface or replace (40/47)
 1/12/12 6:04am
yostusota
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York, PA - USA

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1969 daytona conv. all original 350 350 380 4 sp w/air..and hard top


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The shims you can get it dialed in fine...I just look at everything at what's my time worth..just how I'm wired..I haven't paid anyone to do anything to my cars but I think I may be in a minority just because of what I do and the equipment I have available to me whenever I want to use it.. road trip!!?? Wow that would be a long one!! You ever make it out here and need anything done look me up! Good luck on the last bit of tweaking on the run out!!

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Re: Rotor resurface or replace (41/47)
 2/13/12 1:26am
daveo76
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Vancouver, WA - USA

Vette(s):
1976 Silver/Firethorn. L48, 4spd. Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.


Joined: 8/25/2005
Posts: 857

Finally got my front rotors dialed in - about .003 runout both sides.  Good enough for gov't work (and I do work for the gov't Smile).  Just kept at it with different thicknesses of brash shim stock.  Here are some pics of one of the calipers mounted.  In an earlier post someone wanted to see if you could see the red calipers through the slots in a rally; answer: sort of.  I think a 'vette guy would notice if he were really looking.  Still cool, though - they match my Firethorn (that's red for you non-76'ers) interior.  






|UPDATED|2/12/2012 10:26:20 PM (AZT)|/UPDATED|


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1976 Silver/Firethorn.  L48, 4spd.  Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.
Re: Rotor resurface or replace (42/47)
 2/13/12 7:09am
crossfire1982
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Cramerton, NC - USA

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black 1982 coupe slate gray interior, 350 crossfire, 1985 fuel pump, Steeroids R&P conversion


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Looks good Dave, good work Thumbs Up
Re: Rotor resurface or replace (43/47)
 2/13/12 9:55am
Jaws79Lifetime Member
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Sykesville, MD - USA

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Looking good, Dave! Even if no one else notices, YOU'LL know it's there! So be proud and point it out to all who care! And just think how nicely it will stop!!!!!!!!!
 
Barry
 
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Re: Rotor resurface or replace (44/47)
 2/13/12 1:22pm
yostusota
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York, PA - USA

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1969 daytona conv. all original 350 350 380 4 sp w/air..and hard top


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So..how did the test drive go!!! Glad it worked out for ya!! Paint looks good too...

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Re: Rotor resurface or replace (45/47)
 2/13/12 11:58pm
Adams' AppleLifetime Member
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Duncanville, TX - USA

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#1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas


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SaaaaWEEEET! Looks really nice, Dave! Great job, hangin in there and getting it done!Thumbs Up

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Re: Rotor resurface or replace (46/47)
 2/14/12 3:22am
daveo76
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Vancouver, WA - USA

Vette(s):
1976 Silver/Firethorn. L48, 4spd. Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.


Joined: 8/25/2005
Posts: 857

Thanks for the encouragement, guys.  And thanks for the advice that the three pages of this thread represent!  I'm not sure where I'd be without this forum, but it probably wouldn't be here. Not sure I would have had the courage to tackle some of these projects without this group to lean on.  

Rich: no test drive yet.  Still no engine.  (Or transmission, or steering gear, or master cylinder, or instrument panel, I could go on all day)


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1976 Silver/Firethorn.  L48, 4spd.  Original 2 bolt, vortec heads, 9.4:1 CR, Speed Pro Cam: 224/224@0.050, 112 LSA, Eagle Steel Crank.
Re: Rotor resurface or replace (47/47)
 2/14/12 10:59am
yostusota
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York, PA - USA

Vette(s):
1969 daytona conv. all original 350 350 380 4 sp w/air..and hard top


Joined: 5/18/2010
Posts: 1518

yup!!!!
I know!!
You'll get there...be driving before ya know it!!
and loving every mile of it because you did it yourself!!


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My first parade at Carlisle 2010
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