Question about underhood ...
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Team Owner
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From: Coppin' a tan from the Messiah's aura
St. Jude Donor '08-'09
Question about underhood ...
Noticed two areas underhood where the plastic has discoloration, painting/staining ... is common to cars, but don't know what it is/why it looks that way ... does anyone know background on this?
Driver's side:
Pax side:
Driver's side:
Pax side:
Race Director
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From: Bay Shore, NY 11706 MILD2WILD (M2W)
St. Jude Donor '06-'07
It's most likely the injection point for the resin used to make these fiberglass / composite panels
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From: Wantagh,L.I. New York
Safety Car
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From: Spicewood, Texas, USA TX-Texas
If the dark area has always been there, it's simply a non-critical stain due to a manufacturing anomaly. From the darkness of the area, I'm thinking it falls into this category...think of it as a birthmark.
If it has appeared since the car was new, then it's possible something has been absorbed into the SMC. I learned the hard way...when changing your oil be careful not to drip on the inner fender; the oil will be quickly absorbed into the SMC, and it can not be removed with solvents once its down into the composite. The oil will leave a permanent stain on the inner fender, and I'm sure there are other hydrocarbon based materials (brake fluid, etc.) that will do likewise.
If it has appeared since the car was new, then it's possible something has been absorbed into the SMC. I learned the hard way...when changing your oil be careful not to drip on the inner fender; the oil will be quickly absorbed into the SMC, and it can not be removed with solvents once its down into the composite. The oil will leave a permanent stain on the inner fender, and I'm sure there are other hydrocarbon based materials (brake fluid, etc.) that will do likewise.
Drifting
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From: Roseville CA
If the dark area has always been there, it's simply a non-critical stain due to a manufacturing anomaly. From the darkness of the area, I'm thinking it falls into this category...think of it as a birthmark.
If it has appeared since the car was new, then it's possible something has been absorbed into the SMC. I learned the hard way...when changing your oil be careful not to drip on the inner fender; the oil will be quickly absorbed into the SMC, and it can not be removed with solvents once its down into the composite. The oil will leave a permanent stain on the inner fender, and I'm sure there are other hydrocarbon based materials (brake fluid, etc.) that will do likewise.
If it has appeared since the car was new, then it's possible something has been absorbed into the SMC. I learned the hard way...when changing your oil be careful not to drip on the inner fender; the oil will be quickly absorbed into the SMC, and it can not be removed with solvents once its down into the composite. The oil will leave a permanent stain on the inner fender, and I'm sure there are other hydrocarbon based materials (brake fluid, etc.) that will do likewise.
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Instructor
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From: San Diego CA
If the dark area has always been there, it's simply a non-critical stain due to a manufacturing anomaly. From the darkness of the area, I'm thinking it falls into this category...think of it as a birthmark.
If it has appeared since the car was new, then it's possible something has been absorbed into the SMC. I learned the hard way...when changing your oil be careful not to drip on the inner fender; the oil will be quickly absorbed into the SMC, and it can not be removed with solvents once its down into the composite. The oil will leave a permanent stain on the inner fender, and I'm sure there are other hydrocarbon based materials (brake fluid, etc.) that will do likewise.
If it has appeared since the car was new, then it's possible something has been absorbed into the SMC. I learned the hard way...when changing your oil be careful not to drip on the inner fender; the oil will be quickly absorbed into the SMC, and it can not be removed with solvents once its down into the composite. The oil will leave a permanent stain on the inner fender, and I'm sure there are other hydrocarbon based materials (brake fluid, etc.) that will do likewise.
Don't know if there is another thread on this (and don't want to hi-jack), but since you mentioned the "materials", what exactly are the parts of the Vette made of? How, much of it is still fiberglass? I believe the springs are, but is the body still fiberglass? If not, what is it?
I'll look for the birth marks when I get my car, and will remember not to spill stuff on it! Can't wait!
Safety Car
Joined: Jul 2001
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From: Spicewood, Texas, USA TX-Texas
Don't know if there is another thread on this (and don't want to hi-jack), but since you mentioned the "materials", what exactly are the parts of the Vette made of? How, much of it is still fiberglass? I believe the springs are, but is the body still fiberglass? If not, what is it?
I'll look for the birth marks when I get my car, and will remember not to spill stuff on it! Can't wait!
I'll look for the birth marks when I get my car, and will remember not to spill stuff on it! Can't wait!
The C6 body panels, however, are primarily SMC or Sheet Molded Compound. This is a composite material that is first made into sheets (or maybe large rolls; I'm uncertain of the exact details), and later formed into the desired panel shapes using dies in large presses.
In contrast, the old FRP or fiberglass reinforced plastic body panels (C1, C2, C3) were manufactured by laying fiberglass mat into the lower mold half, adding a measured amount of polyester resin to saturate the mat, and then closing the matched mold halves in a press and adding steam heat through the mold. Body panels made using this method were approximately 0.100" thick...I expect the SMC used today is a fraction of that thickness, but it is tough and flexible to minimize body dings.
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Team Owner
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From: Coppin' a tan from the Messiah's aura
St. Jude Donor '08-'09
Not sure that we've solved the mystery (I can guarantee it's not spilled fluids!) ... but an interesting dialogue. Thanks to all! 
What it may be is combined injectino molding, like two-part epoxy, and there isn't a good flowout at the final part of the injection process, leaving this tell-tale mark. Driver's side photo suggests this may be explanation.
What it may be is combined injectino molding, like two-part epoxy, and there isn't a good flowout at the final part of the injection process, leaving this tell-tale mark. Driver's side photo suggests this may be explanation.
Instructor
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From: San Diego CA
I saw an illustration somewhere (can't remember where) that showed the distribution of plastic materials throughout the C6 Corvette. There were actually a lot more components made out of other reinforced plastic materials than I thought. As you said, there is still some FRP (fiberglass reinforced plastic) parts in a Corvette where additional stiffness and strength is required.
The C6 body panels, however, are primarily SMC or Sheet Molded Compound. This is a composite material that is first made into sheets (or maybe large rolls; I'm uncertain of the exact details), and later formed into the desired panel shapes using dies in large presses.
In contrast, the old FRP or fiberglass reinforced plastic body panels (C1, C2, C3) were manufactured by laying fiberglass mat into the lower mold half, adding a measured amount of polyester resin to saturate the mat, and then closing the matched mold halves in a press and adding steam heat through the mold. Body panels made using this method were approximately 0.100" thick...I expect the SMC used today is a fraction of that thickness, but it is tough and flexible to minimize body dings.
The C6 body panels, however, are primarily SMC or Sheet Molded Compound. This is a composite material that is first made into sheets (or maybe large rolls; I'm uncertain of the exact details), and later formed into the desired panel shapes using dies in large presses.
In contrast, the old FRP or fiberglass reinforced plastic body panels (C1, C2, C3) were manufactured by laying fiberglass mat into the lower mold half, adding a measured amount of polyester resin to saturate the mat, and then closing the matched mold halves in a press and adding steam heat through the mold. Body panels made using this method were approximately 0.100" thick...I expect the SMC used today is a fraction of that thickness, but it is tough and flexible to minimize body dings.
Thanks for the info! That's what I like about the forum - knowledgable (sp?) people.
So, does that mean what I think it does? That the cars are similar in their abiltiy to resist "door dings" like older Saturns were? Don't own the car yet (ordering in the next 2 weeks), and didn't want to kick too many on the dealers lots to find out.
Cool....
Safety Car
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From: Spicewood, Texas, USA TX-Texas
Probably...I haven't "kicked" any newer Corvettes, but the panels seem to flex easier under pressure than the old ones. That means that panels can take more deflection from minor impacts and spring back. Of course, the paint can't be as flexible as the panels...there is no permanent deformation of the panel, but paint cracks or chips will still happen.
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St. Jude Donor '05-'06-'07-'10
I saw an illustration somewhere (can't remember where) that showed the distribution of plastic materials throughout the C6 Corvette. There were actually a lot more components made out of other reinforced plastic materials than I thought. As you said, there is still some FRP (fiberglass reinforced plastic) parts in a Corvette where additional stiffness and strength is required.
The C6 body panels, however, are primarily SMC or Sheet Molded Compound. This is a composite material that is first made into sheets (or maybe large rolls; I'm uncertain of the exact details), and later formed into the desired panel shapes using dies in large presses.
In contrast, the old FRP or fiberglass reinforced plastic body panels (C1, C2, C3) were manufactured by laying fiberglass mat into the lower mold half, adding a measured amount of polyester resin to saturate the mat, and then closing the matched mold halves in a press and adding steam heat through the mold. Body panels made using this method were approximately 0.100" thick...I expect the SMC used today is a fraction of that thickness, but it is tough and flexible to minimize body dings.
The C6 body panels, however, are primarily SMC or Sheet Molded Compound. This is a composite material that is first made into sheets (or maybe large rolls; I'm uncertain of the exact details), and later formed into the desired panel shapes using dies in large presses.
In contrast, the old FRP or fiberglass reinforced plastic body panels (C1, C2, C3) were manufactured by laying fiberglass mat into the lower mold half, adding a measured amount of polyester resin to saturate the mat, and then closing the matched mold halves in a press and adding steam heat through the mold. Body panels made using this method were approximately 0.100" thick...I expect the SMC used today is a fraction of that thickness, but it is tough and flexible to minimize body dings.
Here is the illustration from the C5 days, most of it applies to the C6 as well.