C3 front spring color + misc

[Eli Robinson]

I am currently doing a frame on rebuild of a 68 coupe. This car was minorly crashed sometime between 80 and 85 as it was last registered in 85ish and was wearing a very poorly grafted 80-82 style bumper up front. The rest of the front fiberglass was in generally poor condition and I decided to replace it as I already had two new fenders (see below). I have repainted the frame (except under the tub on top) a semi gloss black and am in the process of freshening the front and rear suspension with new bushings. All hard parts were in good condition with no slack. All control arms are being painted off the car. My question is what color should the front coil springs be painted? I have found elsewhere in the archives that Krylon dove grey #1605 is correct enough for the rear spring atleast on C2s. Does this apply to C3s? Is this the same color as the front springs? I do not hope to achieve NCRS standards this go round with the car as I am on a bit of a budget, but would like it to be presentable and not glaringly wrong. For now, it will be a driver. I do have the original 327 and turbo 400 to go back in. And I am planning to check my casting numbers on things like brake calipers before I blindly turn them in as cores. When I bought the car I received two NOS GM press molded front fenders (a few cracks from storage but definately useable) so I plan on purchasing a PM hood surround. The hood is fine, original and already prepared for paint. I can reuse my passenger side inner fender but the driver side was damaged in the crash. Also, what is everyone using to reseal the seam between the firewall fiberglass and the front hoop? My windshield frame is not rusty but the (aluminum?) rivets that hold the firewall fiberglass to the hoop have corroded and gave way allowing the firewall to seperate slightly. I plan on coating this area with a rust preventative before reattaching the firewall but did not know what sealer is correct or what will pass as correct. I don't want to shoot myself in the foot doing something now that i would have to undo at considerably more expense later if it only cost slightly more to do it "correct". Are the rivets hardware store pop rivets? Sorry for the long winded post!

Thanks,
Eli

[Steve Wallach]

Re: C3 front spring color + misc

The grey for the rear spring is probably close enough. The front springs should be "natural", but I use Stainless Steel spray paint with a light coat of clear. As for the firewall to the bird cage, you should use Green Chromate primer on the bird cage. As for the "Sealer", white body sealer is correct for between the fire wall and the bird cage.

Hope that helps,

Good Luck,

Steve

[Eli Robinson]

Re: C3 front spring color + misc

thanks! would a media blasting of the springs + clear work as well? Is the green chromate primer the same stuff as used in marine applications?

Thanks for the help,
Eli

[Steve Wallach]

Re: C3 front spring color + misc

media blasting would work for the springs with a light coat of clear for some rust protection.

Green Chromate is the same as used in Marine applications, and you can get it from any Corvette Supply company.

Cheers,

Steve

[Chuck S.]

Re: C3 front spring color + misc

It sounds like you are going to have to rebond the fiberglass to the body frame or "bird cage". Inspect all the front fender and firewall bonds to the bird cage. If you don't have it already, buy the 68 AIM (Assembly Instruction Manual)...it will have details on the types of bonds used at different locations, and it will be invaluable throughout your restoration.

If I'm not mistaken, the aluminum rivets are there to only reinforce a fiberglass to primed steel bond...that residue is adhesive not sealant. If I were you, after cleaning and priming the body frame and roughing up the firewall fiberglass, I would bond the firewall back with a modern adhesive like Lord Fusor. For originality, I would be inclined to use polyester based adhesive that was originally on all the body panel bonds. Some would say use the Lord Fusor everywhere, but that's just me.

If the rivet heads are in place, just leave them for show...no one will know that they are only riding along. I don't think you can get an exact duplicate of those rivets at home stores. You can find a functional replacement, but the heads will be lighter duty and have diffent appearance.

[Eli Robinson]

Cowl rivets and fiberglass rebonding + misc

I don't have the AIM yet. I think I will order one today or tomorrow. I think ome of the rivet heads have actually fallen off. I currently have the fiberglass stripped off the car from the cowl forward. When removing the driver side fender, the little filler piece at the corner of the windshield came with the fender. I suspect the bond here was weakened in the past collision. I also have to replace a passenger side rear quarter due to extreme wheel opening damage, presumably from a blown out tire. While my car has obviously been through alot, I still think i got a great deal on a the car when i bought it ~3 years ago. I paid more for the engine than for the car! The PO had sent the engine to a local well known machine shop to be rebuilt. He offered me the car and the engine or just the car. After confirming the VIN matched on the engine and seeing the build sheet for the engine, i decided it would be most prudent to buy both. I wish I knew the stories it has lived through. I will investigate further tonight concerning my rivets. I will have to also take a picture of the seats, I almost hate to destroy such a work of umm art, covered in button tufted maroon and black crushed velour with pillow tops! Thankfully I think these are covers simply slipped over the original with an intact set of original seat foams. They are comfortable though..............but the height the extra padding adds makes my head hit the t-top panel.

Thanks for all the help
Eli

P.S. I changed my subject in case anyone is searching for this later. I searched and searched but never could turn up much on the subject of reattaching the firewall.

[Travis Williamson]

Re: C3 front spring color + misc

Eli

On my 70, I media blasted my springs and steering knuckles used the Clear Eastwood Rust Encapsulator. I havent installed them yet to see how well the stuff holds up on the springs but so far they look great.

http://www.eastwoodco.com/jump.jsp?itemID=12237&itemType=PRODUCT

The NCRS Technical Information Manual & Judging Guide is a great guide. Not everything is in it, but it contains a lot of valuable information. Well worth it in my opinion.

Travis

[Terry M.]

C3 front spring color

Coil springs as used on our Corvettes are formed hot -- glowing red-hot. Wire (yes, even in the diameter used for coil springs the material is called wire) is rolled into a coil while it is red-hot. As it cools a slag (covering) will form on the wire. This slag is blue/gray -- just like on stabilizer bars. As the spring is handled in manufacturing some of that slag will flake off. Some springs are shot blasted after cooling to remove the slag and add a surface treatment to the spring. If shot blasted, the color of the spring will change from the blue/gray of the slag to a lighter gray. I do not believe that the Corvette front coil springs were shot blasted, but someone with the print needs to read the notes to tell us the process specifications.

[Patrick H.]

Re: C3 front spring color

Terry,

I thought that Michael Hanson had posted a picture once of C3 springs in St. Louis. They were definitely a lighter color, what you might even call a dull silver. IIRC he thought they'd been shot blasted and then coated with some type of heavy preservative similar to CRC 350.

Patrick

[Terry M.]

C3 front spring color

I would love to see that, even if it is a repeat for some folks. It will be new for me.

[Patrick H.]

Re: C3 front spring color

Search the April 05-to-now Archives with the term "CRC 350" and the post by Michael regarding the 72 front springs. Read that thread, although the picture is now gone.

I'll e-mail him about the photo.

Patrick

[Michael H.]

Re: C3 front spring color

Terry,

Hope this is the pic that Patrick was refering to. Front coil springs were just as it appears in the photo. Silver in color with a slight reflectivity. This would be the case for C2 and C3. (not sure about C1)

Springs, as shipped to the plant, had a thin, almost invisible coating of rust preventative that included cosmoline in the mix. One such coating that's probably still available today is SP-350 by CRC.

[Terry M.]

Re: C3 front spring color

Thanks Michael and Patrick. Somehow I missed tht photo when it was first posted. Yes, that is what shot blasting looks like. That makes recreating that finish easy.

[Patrick H.]

Re: C3 front spring color

That's the one.

[Dick W.]

Re: C3 front spring color

Terry, I just sent an Email to Franz asking him about the treatment after heat.