Author Topic: Painting 12 bolt Differential detail Questions  (Read 6730 times)

68camaroz28

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Painting 12 bolt Differential detail Questions
« on: November 27, 2011, 02:40:39 AM »
When the differentials were painted originally I've read and researched they were of course painted as a completed assembly with the emergency cables attached but no brake lines and that the yoke and emergency cables were protected from paint with a cardboard sleeve or some type of protection.
1. Was the wheel cylinder brake fluid bleeder installed after paint or before. Other words, should it be bare metal or painted? I assumed bare metal but found traces of black paint on one of ours.
2. On the emergency brake cables, how much black paint was normally on them? 
Thanks for any assistance as we need to get this rear finished ;D
Chick
68 Z/28 NOR 01B Orig motor/trans/rear
69 Z/28 NOR 07A Orig Block & GM Cross-ram/carbs
69 L34 Rest. Nova Father/Son Car
69 L78 Surv Nova Purch 4/69 31K miles
67 L89 Corv Tribute
68 Corv 427/400 Orig motor
07 Corv Z06
R 68Z build- http://www.camaros.net/forums/showthread.php?t=182584

JohnZ

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Re: Painting 12 bolt Differential detail Questions
« Reply #1 on: November 27, 2011, 05:56:15 PM »
When the differentials were painted originally I've read and researched they were of course painted as a completed assembly with the emergency cables attached but no brake lines and that the yoke and emergency cables were protected from paint with a cardboard sleeve or some type of protection.
1. Was the wheel cylinder brake fluid bleeder installed after paint or before. Other words, should it be bare metal or painted? I assumed bare metal but found traces of black paint on one of ours.
2. On the emergency brake cables, how much black paint was normally on them? 
Thanks for any assistance as we need to get this rear finished ;D

The wheel cylinder bleeders were in place when the axle was painted, and the degree of coverage on the parking brake cables varied - there will be more at the drum end, and less away from the drum.
'69 Z/28
Fathom Green
CRG

william

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Re: Painting 12 bolt Differential detail Questions
« Reply #2 on: November 27, 2011, 06:06:47 PM »
I have virtually every 67-70 car magazine that featured a 1st gen Camaro. There were very few rear axle photos and few show the backing plates.

For your purposes by far the best photos are in the May 1968 Rodder & Super Stock. The article is titled “Super Bite for the Camaro.” The article details the installation of traction bars and reinforcing welds on a new ’68 Camaro SS axle. The photos are b & w on pulp and aren’t the best. However viewing these and comparing to others leads me to believe everything was in place when the axle was painted. However the bleeders may have had caps on them as they don’t appear painted some photos. The E-brake cables appear to have some overspray on them approximately 2/3 of their length-not completely painted.

The same ‘68 is featured in the March 1968 Hi-Performance Cars. There is an excellent photo of the left end of the axle clearly showing two important details: the brake drum is completely painted as is the end of the axle. The clip used on one stud to keep the drum in place is easily visible and not painted.

There is another axle photo in the June ’68 PHR of the famous Nickey/Bill Thomas 427 conversion.
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169INDY

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Re: Painting 12 bolt Differential detail Questions
« Reply #3 on: November 28, 2011, 06:20:57 AM »


There is another axle photo in the June ’68 PHR of the famous Nickey/Bill Thomas 427 conversion.


Along with the rear end detail shot on page # 27 , btw I like those Thomas traction bars!

Page # 24 Clearly shows the fact that crayon marks were in fact made on top of the firewall black out treatment!

If I only had a time machine I would not touch a Motion super car, but have a stable of Thomas & Harrells SUPERCARS!

Jim
Jim
68 SS/RS L35 Th-400 LOS
69 Pace Car L48 Th-350 LOS
68 Z28 M21 LOS

NoYenko

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Re: Painting 12 bolt Differential detail Questions
« Reply #4 on: February 26, 2012, 04:55:19 PM »
Chick, Thanks for all the info you post, it has been a big help to my restoration. I just finished my diff. thought I would pass along what info I found & ask for advice.
My car is an 11A Nor built car. I assumed the car build started Nov 3-9 1968, but the diff was stamped Nov 11Th and the inspection stamp date on the brake adjuster is Nov 16 (316). I thought you posted a picture of your stamp date but I can't find it.
My diff had very little paint on it but the backing plates had very thick black paint. They were dipped & hung because the paint was thickest at the top of the plate. My brake adjuster arm was dark in color kind of a dark blue-black color, I think it was dark phosphate. My springs were the same colors that you found, but I didn't find any paint on the brake shoe retainer caps. The large nut holding the top shoe pivot was copper plated. After cleaning, plating & assembling everthing it kills me to paint over it. I really don't like the look of paint on the parking brake cables, looks sloppy but correct I guess. I would like to get my car judged after I complete it, and I wonder if a judge would deduct points without paint on the cables & bolts. What would you and others do?

NoYenko

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Re: Painting 12 bolt Differential detail Questions
« Reply #5 on: February 26, 2012, 04:58:16 PM »
With & without paint photos.

william

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Re: Painting 12 bolt Differential detail Questions
« Reply #6 on: February 26, 2012, 05:10:22 PM »
Are you restoring the car as the factory built it or are you building a show car?

Photo #1 is how the factory built it except there would be paint coverage on the drums. Overspray on the cables is about right. Remember no surface prep; paint did not adhere well.

They built 57 Camaros per hour. No time to primer-fill, wet-sand, polish stuff.
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NoYenko

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Re: Painting 12 bolt Differential detail Questions
« Reply #7 on: February 26, 2012, 06:10:09 PM »
My desire is to restore it to as it left the factory, but just a little nicer, cleaner, and more durable for street use. Does that even make sense?
An example, my diff housing I tried to do a light powder coating so that it was more durable than paint, but backing plates that see less abuse I painted. George.

big iron

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Re: Painting 12 bolt Differential detail Questions
« Reply #8 on: February 26, 2012, 07:00:03 PM »
I wonder how the assemblies where suspended for painting . That in it's self would indicate to what extent areas received the most paint.
Bob

68camaroz28

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Re: Painting 12 bolt Differential detail Questions
« Reply #9 on: February 26, 2012, 07:29:15 PM »
George, thanks for the kind words. Here is the stamping on our adjusters. Assume it is '332'!
http://www.camaros.net/forums/showthread.php?t=182584&page=27
IMHO, a cleaner look is non-painted hardware and since you have the backing plates painted and the rear powdercoated that may make more sense. For me, it was an original look so everything was painted but to control the overspray on the emerg. cables they were painted at the same time but not installed so we could control the amount of overspray and fade out.
Now as far as holding up if you decided not to paint make sure you protect that hardware or after a few years it will show its age. So far I'm liking that "rust prevention magic!"
And what you have completed looks extremely nice. Nice work and good on ya!!!!!!!
P.S. See my other post concerning your rear brake bracket update.
Chick
68 Z/28 NOR 01B Orig motor/trans/rear
69 Z/28 NOR 07A Orig Block & GM Cross-ram/carbs
69 L34 Rest. Nova Father/Son Car
69 L78 Surv Nova Purch 4/69 31K miles
67 L89 Corv Tribute
68 Corv 427/400 Orig motor
07 Corv Z06
R 68Z build- http://www.camaros.net/forums/showthread.php?t=182584