Dinged carbon fork, unsure if on alloy or carbon portion
10-05-15, 01:27 PM
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Dinged carbon fork, unsure if on alloy or carbon portion
I dinged a carbon CX fork loading the bike into a car (actually, I think I trapped it between folding seats with the wheel out) and have chipped what I think is just a small flake of paint off the 'shoulder' of the bottom of the fork blade immediately above the inside face of a dropout.
I'm very wary of damage to carbon (especially a fork), but it looks to me like the surface under the paint is Al, which makes me think that some portion of the bottom of the blade is Al in addition to the dropout 'proper'. Certainly it's painted opaque black and only becomes the 'ooh, carbon!' transparent about an inch above.
Is there a clever and non-destructive way to confirm where the Al stops and the carbon begins?
If I can confirm it's just paint chipped off an Al surface, then I'll touch it up and keep an eye on it.
Fork is a Fuji FC-990. The dropout 'blends' into the fork blade - this is not my fork, but visually similar design in the dropout area to this FC-770 (photo stolen from ebay) except that mine has an eyelet and drain hole:
I'm very wary of damage to carbon (especially a fork), but it looks to me like the surface under the paint is Al, which makes me think that some portion of the bottom of the blade is Al in addition to the dropout 'proper'. Certainly it's painted opaque black and only becomes the 'ooh, carbon!' transparent about an inch above.
Is there a clever and non-destructive way to confirm where the Al stops and the carbon begins?
If I can confirm it's just paint chipped off an Al surface, then I'll touch it up and keep an eye on it.
Fork is a Fuji FC-990. The dropout 'blends' into the fork blade - this is not my fork, but visually similar design in the dropout area to this FC-770 (photo stolen from ebay) except that mine has an eyelet and drain hole:
10-05-15, 01:53 PM
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If you insist... 
The 'new' ding is the chip at about 1 o'clock from where the axle center would be in this photo. It has a slight sharp edge at the top corner. I think that whole section is alloy, but not completely certain.
The 'new' ding is the chip at about 1 o'clock from where the axle center would be in this photo. It has a slight sharp edge at the top corner. I think that whole section is alloy, but not completely certain.
10-05-15, 01:55 PM
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I would paint it with some nail polish or Testers hobby paint. Looks like a paint chip on the aluminum dropout.
10-05-15, 02:01 PM
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Yeah, that's what I thought too. But I don't know how the dropout is attached to the carbon portion of the blade on this style of fork or whether that section would 'typically' be carbon or Al.
Presumably the raw dropout for a fork like this looks nothing like the flat plate that is inserted into steel forks (or if it is, it's welded into a Al 'carrier' that caps the bottom of the fork blade).
Presumably the raw dropout for a fork like this looks nothing like the flat plate that is inserted into steel forks (or if it is, it's welded into a Al 'carrier' that caps the bottom of the fork blade).
