Is my frame cracked?
06-05-15, 09:26 AM
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Is my frame cracked?
My frame is 6061 Aluminum. I've noticed this for about a year but it's possible it could have been there longer. I think it may have grown but I'm not confident enough to say for sure. Maybe it's just an odd weld with paint that has come off? it's kind of shaped like this < as you can tell from the pics. It's on the rear triangle.
If this is a crack what should I do? I've heard 6061 is near impossible to find a welder for because you have to reheat the weld to bring up the strength. I've heard of people coating cracks with super glue but I don't believe that will do much. I guess it's better than nothing. THANK YOU
If this is a crack what should I do? I've heard 6061 is near impossible to find a welder for because you have to reheat the weld to bring up the strength. I've heard of people coating cracks with super glue but I don't believe that will do much. I guess it's better than nothing. THANK YOU
Last edited by BradMitch; 06-05-15 at 09:48 AM.
06-05-15, 09:33 AM
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Doesn't appear to be, from what I can see in pictures. Take it to a welder or a good bike mechanic
06-05-15, 09:35 AM
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I am no expert but it looks like a part of the weld which did not stick, not a crack. I suspect that it has been there all along. Photo 2 especially shows that it was never a part if the weld fillet. I would ride it, myself, but keep an eye on it.
06-05-15, 09:42 AM
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That is one nasty weld to begin with....sloppy work.
06-05-15, 09:45 AM
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Yeah I thought I didn't look like cracks I've seen. Thanks so much Blue Belly, dsbrantjr, and RPK 79! I'm debating if I should rub some glue over it. I guess I may just as an extra precaution although I've heard it gets stronger with water rather than rust/corrosion. Lol at the 8ball
Last edited by BradMitch; 06-05-15 at 09:49 AM.
06-05-15, 09:46 AM
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Just an ugly weld, I think. Not cleaned up properly. But take it to a bike mechanic to be safe.
06-05-15, 11:38 AM
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Nice that you posted three images that all show what needs to be seen. Doesn't always happen on BF.
Looks sloppy, not broken, to my untrained eye.
Looks sloppy, not broken, to my untrained eye.
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06-05-15, 11:46 AM
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May be, a dye penetrant test will tell and the paint will have to come off.
06-05-15, 11:59 AM
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Crack or not crack, it really doesn't make a difference from a prevention or outcome basis.
It's been there a year or so, and odds are it's not going anyplace. But even if it were, there's nothing you can really do to change that, and if it were to fail while riding, it's not likely to cause a crash.
In normal use, chainstays are in compression from chain load, so if it cracks, there'll be some movement and creaking/clanking but the chain and rear axle will work to keep things pretty much where they are, and you won't crash.
That said, you might either ignore it, or clean the crack with water, dry it and fill it with paint. This obviously doesn't add strength, but it will prevent corrosion from trapped salts or other stuff and in doing so will slow any tendency to get worse and ultimately fail.
It's been there a year or so, and odds are it's not going anyplace. But even if it were, there's nothing you can really do to change that, and if it were to fail while riding, it's not likely to cause a crash.
In normal use, chainstays are in compression from chain load, so if it cracks, there'll be some movement and creaking/clanking but the chain and rear axle will work to keep things pretty much where they are, and you won't crash.
That said, you might either ignore it, or clean the crack with water, dry it and fill it with paint. This obviously doesn't add strength, but it will prevent corrosion from trapped salts or other stuff and in doing so will slow any tendency to get worse and ultimately fail.
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An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
06-05-15, 01:59 PM
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