Carbon Fiber Painting problems at BG

[LongTimer]

Z16s Are Now Ready To Roll!
C5 Registry Members – Great news! The word’s just in that the carbon fiber hood/paint issue which had stopped Commemorative Z06 production has been solved. Our hats off to the hard working folks at our favorite toy store who spent countless weeks and hours finding a solution so that this very limited performance C5 can once again be ready for our members waiting arms! Word is Z16 production should be in full swing by mid-October so they will be able to reach their goal of 2,100 Commemorative Z06s produced for the USA market. Currently it is estimated that only a handful of Z06/Z16s that have been shipped to a very few dealers.

If any body pannels were designated to the CF in the C6, I have to believe that this problem would have been identified and resolved long ago. My guess is that some CF might be used to reduce weight of "hidden" parts especially in the interior. THIS IS JUST A GUESS, but maybe the seat structures under the leather and / or console under some brushed Al or something like that???

 

[Vettelt193]

Many times GM will test parts, paint, etc out on limited run cars so they can work out the problems before the problem is too big to handle. Imagine if the entire factory came to a standstill because every car had a carbon hood... By making it just a limited run, all the kinks are worked out, and they can be sure they won't have any issues if every C6 has carbon fiber parts.

 

[LongTimer]

Many times GM will test parts, paint, etc out on limited run cars so they can work out the problems before the problem is too big to handle. Imagine if the entire factory came to a standstill because every car had a carbon hood... By making it just a limited run, all the kinks are worked out, and they can be sure they won't have any issues if every C6 has carbon fiber parts.

Makes since - and makes my point. Would Hill commit to a C6 with - say CF hood, fenders, and doors, then not test the production paint process until 3.5 months before introduction?
I don't think so. IMO. Maybe just the hood, because if it didn't work out, they could switch back to Fiberglass with only a 10lb penalty from their target.

 

[Edmond]

Makes since - and makes my point. Would Hill commit to a C6 with - say CF hood, fenders, and doors, then not test the production paint process until 3.5 months before introduction?
I don't think so. IMO. Maybe just the hood, because if it didn't work out, they could switch back to Fiberglass with only a 10lb penalty from their target.

How does the strength of CF compare to fiber glass? I'm sure they'd have to get the CF panels approved for crash tests as well right?

 

[LongTimer]

I'm no engineer, but I'ver heard them say that CF pannels can be thinner and much stronger than FG. But your point is well taken. If the CF is part of the crash structure, it needed to be tested by the gov. Again, a long lead commitment. Painting would have been tested long before now.

 

[Edmond]

Vettelt193,

I think your theory is pretty good. Yep, they'll test out a few select parts on some C5's and if they're good to go, they'll have that experience for the C6. They'll be able to anticipate any problems that come up.

Was it even confirmed that CF would be extensively used for the C6?

 

[LongTimer]

Vettelt193,

Was it even confirmed that CF would be extensively used for the C6?

NO. It has been part of the possibilities guessed at by many as to how the C6 can shave weight from C5 (300 lbs?). I can't see them waiting until now to test exterior painting of CF, if they had commited to extensive exterior CF in the C6. So, I am no longer expecting to see significant CF usage in the C6.

 

[99WhiteC5Coupe]

Vettelt193,

Chevrolet has tested parts on many C5's so they could work out problems.

Some of the parts that come to mind are the column lock module, rear differential o-ring seals, lighter weight power seat adjusters, fuel tank modules, thin leather seat covers, batteries that leak acid, a/c drains that clog, etc. etc.

 

[CFour]

Oh hell, my dealer here in Chicago has not one but two 04 Colletor edition Z06s on the showroom floor (one even used). They are nothing to drool over. Looks like a Blue Corvette with a bunch of stickers on the hood. You can not really tell the hood is different from a standard hood from the outside. Ahhhhhh expect to see this type of hood standard on C6 and maybe some other C/F pieces too.....

 

[Rob]

I'm not a materials engineer, so does anyone know how carbon fiber compares to Kevlar in terms of weight and strength?

I'm just kind of curious because I believe that the 1st and 2nd generation Vipers came with hoods that were either all Kevlar or a carbon fiber/Kevlar composite. I'm curious if Corvette Engineers have tested/compared both products when they were developing the hood for the Comm. Z06.

 

[Edmond]

I'm not a materials engineer, so does anyone know how carbon fiber compares to Kevlar in terms of weight and strength?

I'm just kind of curious because I believe that the 1st and 2nd generation Vipers came with hoods that were either all Kevlar or a carbon fiber/Kevlar composite. I'm curious if Corvette Engineers have tested/compared both products when they were developing the hood for the Comm. Z06.

Rob,

I remember reading an article that said kevlar has higher tensile strength than steel so I think it would be much stronger than CF. Kevlar can stop bullets and fragmentation so it must be strong!:L:L:L

But I think kevlar would be extremely expensive. As for those Viper hoods, I remember reading on some Viper site about an individual who sold those hoods of the customers' vehicles that he was hired to tune. Those hoods bring big money. But it would be fascinating though....a bullet proof engine combined with bullet proof body panels....we'd have a real life Bat Mobile!

 

[CFour]

Indeed, Kevlar "right now" is to expensive for a mass produced automobile. C/F is also easier to shape/form into body panels.

 

[hippy]

Another thread where the blind lead the blind. I'm no expert on composites, but I'm guessing the one course I have taken (intro to composites) and my limited work with fiberglass + polyester is more than those who are offering up answers. Kevlar is a DuPont fiber, I don't recall exactly what its tensile strength is off the top of my head, but to the guy who said 'it's stronger than steel so it must be stronger than CF' is on crack. I believe Kevlar is 'tougher' than CF, but if I had to guess CF is much stronger. Tougher as in it will sustain a greater deformation before yielding. Carbon fiber is extremely strong, that's why you can 'use less' and still have a 'stronger' part. Either could be used to make body panels that are lighter.

And on to the matter of which will hold up better in an accident. How strong something is, by which i mean Young's modulus, is not a very good indicator of how well a material will perform in an impact. What you want to happen in an impact is energy absorption, your car takes the beating so you don't have to. How well do you think FG absorbs energy? Not sure? Take a big hammer and smack your vette, did you make a dent or a crack? Probably a crack. FG, CF, and most all composite structures are brittle. Brittle materials do not absorb energy well, and thus do not provide a good source of protection in a collision. That's why the corvette chassis is made of metal, currently steel, that is meant to absorb the energy from an accident. I highly doubt anybody sat down and tried to conteplate the ramifications of putting CF body panels onto a car that already had a body that doesn't do much for you in a collision. If you think I'm wrong, and believe FG is great in accident, get one of those FG dune buggies and run it into a wall. Send me pictures to illustrate your points.

 

[Edmond]

Another thread where the blind lead the blind. I'm no expert on composites, but I'm guessing the one course I have taken (intro to composites) and my limited work with fiberglass + polyester is more than those who are offering up answers. Kevlar is a DuPont fiber, I don't recall exactly what its tensile strength is off the top of my head, but to the guy who said 'it's stronger than steel so it must be stronger than CF' is on crack. I believe Kevlar is 'tougher' than CF, but if I had to guess CF is much stronger.

Hi,

First of all, welcome to the Corvette Action Center.

I would also like to thank you for insulting me and the rest of the members here on this forum.

I was the one who guessed that "it's stronger than steel so it must be stronger than CF." Thank you for insulting me; and no, I am not on crack.

The members here on the forum are not blind.

That is all I will say. I'm sure Rob will read your post and deal with you for making offensive comments like that. I'm not a moderator or administrator on this forum. But I do know that we don't operate by calling people names or insulting their intelligence.

 

[CFour]

Oh, Thank God im not the only trouble maker here.....

 

[Rob]

Another thread where the blind lead the blind. I'm no expert on composites, but...

Hell of a way to make an introduction here.

This is an online community composed of people from all walks of life, and sometimes, the blind leading the blind is the best that we can do when it comes to helping one another out.

I apologize that we can't all be experts in our field, so by all means, please enlighten us with your wisdom, knowledge and tact.

 

[ROCKETBLOCK]

I have a dumb question along the Kevlar, Fiberglass, Carbon Fiber line. What parts of the Corvette body are Fiberglass any more? I thought we were now using a new type of plastic panels??? Go easy! I said it was a dumb question!

 

[Rob]

I have a dumb question along the Kevlar, Fiberglass, Carbon Fiber line. What parts of the Corvette body are Fiberglass any more? I thought we were now using a new type of plastic panels??? Go easy! I said it was a dumb question!

Not a dumb question at all and in fact, there is no part of the Corvette body that is fiberglass and I don't believe it really has been fiberglass since the days when Sharks ruled the roads; maybe even earlier, but I'm not sure off the top of my head.

EDIT:
I stand corrected, please see post below.

Starting in '84, the Corvette used a special Sheet Molded Composite or SMC. I believe that the composition changed from C4 to C5. You can read more about it here:

http://corvetteactioncenter.com/tech/c5/smc.html

http://corvetteactioncenter.com/tech/c5/smcroof.html

 

[CFour]

Corvettes are indeed fiberglass. They are made from SMC (Sheet Molded Composite) Instead of hand laying the fiberglass compound is pressed into forms with high pressure and heat. The basic components are very much the same however.

 

[Rob]

Corvettes are indeed fiberglass. They are made from SMC (Sheet Molded Composite) Instead of hand laying the fiberglass compound is pressed into forms with high pressure and heat. The basic components are very much the same however.

It was my understanding that there are no glass fibers in SMC? Am I wrong?