need help top tube ding!
04-01-11, 02:28 PM
#1
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need help top tube ding!
hello fellow bikers!
wondering if any one has a trick to remove a dent/ding on a top tube caused by me falling. (handle bars clocked back and dented/dinged my top tube)
ohh i almost forgot its an aluminum 2.8 cannondale frame 97
or does anyone have any suggestions?
wondering if any one has a trick to remove a dent/ding on a top tube caused by me falling. (handle bars clocked back and dented/dinged my top tube)
ohh i almost forgot its an aluminum 2.8 cannondale frame 97
or does anyone have any suggestions?
04-01-11, 04:32 PM
#4
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wrap the spot with handlebar tape, rubber and colored electric tape, etc,
so it will not be seen and make some bumper for the next time.
so it will not be seen and make some bumper for the next time.
04-01-11, 05:41 PM
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Aluminum cannot be popped or eased back to shape like you would with steel frames using frame blocks. Problem is, aluminum is soft and it stretches much more than steel so the deformation is pretty much permanent (specially in thicker gauges) as the stretched material does not have anywhere to go. plus Al does not like to be bent around too much as the material will crack.
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04-01-11, 07:52 PM
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With steel there are a number of techniques for working a dent back, aluminum shouldn't be worked at all. The dent is done, and may or may not lead to stress cracking down the road, probably wa-a-a-y down the road. But you don't want to worsen your situation buy working it farther to "improve" the dent. Cover or camouflage it, or whatever makes you happy, otherwise leave bad enough alone.
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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.
04-02-11, 02:02 AM
#8
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Typically with the aluminiums we use you get one "free" bend. Then if you try to bend it again it cracks. So likely you're stuck with this one.
Having said this after talking to a buddy that was an aircraft sheet metal worker I learned of a trick. To bend high "T" value alloys or forged alloy parts that got bent, motorcycle clutch levers in my case, he suggested blackening the bent area with a candle or lighter. Then once nicely blackened to heat it with a propane torch until the carbon blackening was gone. The alloy would then be stess relieved enough to bend the levers back. It worked for two levers. One I still have and use and the other was sold on the bike it was mounted on some years back. The idea is that the heating of the metal relieves the bending stresses enough that you get your "one free bend" back and can use it to straighten the part. So far I've only used int on bent clutch levers because I'm not so cheap as to try it on a brake lever.
This trick may have some application to your situation but first you'd need a way to push from the inside and also you'd need to remove the paint back for quite some distance from the dent due to the need to carbon the metal and then heat it with a propane torch. All of which would blister the metal badly for many inches to either side if the paint was left on.
The only problem is that even if it does do the job
Having said this after talking to a buddy that was an aircraft sheet metal worker I learned of a trick. To bend high "T" value alloys or forged alloy parts that got bent, motorcycle clutch levers in my case, he suggested blackening the bent area with a candle or lighter. Then once nicely blackened to heat it with a propane torch until the carbon blackening was gone. The alloy would then be stess relieved enough to bend the levers back. It worked for two levers. One I still have and use and the other was sold on the bike it was mounted on some years back. The idea is that the heating of the metal relieves the bending stresses enough that you get your "one free bend" back and can use it to straighten the part. So far I've only used int on bent clutch levers because I'm not so cheap as to try it on a brake lever.
This trick may have some application to your situation but first you'd need a way to push from the inside and also you'd need to remove the paint back for quite some distance from the dent due to the need to carbon the metal and then heat it with a propane torch. All of which would blister the metal badly for many inches to either side if the paint was left on.
The only problem is that even if it does do the job
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