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Old 05-25-12, 09:30 AM   #1
escarpment
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Cracked lug, can I fix it with epoxy?

I was given an old steel reynolds 530something frame and there is a crack in the lug where the top tube and head tube meet. I am curious if I can use epoxy to fill the gap, The frame itself is still structurally sound it is just the top part of the lug that has a crack.
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Old 05-25-12, 09:43 AM   #2
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i would see if you could get it filled with braze from a bike builder or engineering shop as the lug has craked it may have craked the braze too and that would lead to the frame braking more than likley when your on it too which would be a trip to A&E.
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Old 05-25-12, 10:26 AM   #3
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Rarely is epoxy a good fix but it may work. Pics would certainly be a help here.

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Old 05-25-12, 12:26 PM   #4
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The actual tensile strength of Epoxy is way below that of any metal, even brazing brass. I would have the lug repaired by brazing, or better yet, have it replaced by a competent frame builder.
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Old 05-25-12, 01:14 PM   #5
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From the title I was expecting a carbon tubed frame.

Epoxy to repair steel? Maybe cosmetically. If you are worried about the structural integrity of the frame get it brazed/welded properly.
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Old 05-25-12, 01:37 PM   #6
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Pictures would help us determine if this is more than just a cosmetic flaw. If it is in fact a structural concern, epoxy is not a solution.
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Old 05-25-12, 01:56 PM   #7
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Unlike BB. Seat Cluster and dropouts, playing loose the headtube junction like with fork crowns is risky business.

Seriously conisder having a frame builder look at it.

=8-)
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Old 05-25-12, 02:57 PM   #8
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A frame builder would be what I would consider an expert for the situation.

The other day I had a muffler put on and the guy welded the exhaust pipe. It does not take much to impress me. I was impressed by the way the weld looked. I don't have a clue as to how strong a weld like that would be. Just a thought to be considered.
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Old 05-25-12, 03:12 PM   #9
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I can't imagine that it could be properly fixed without a major repair. As above, good pictures are required
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Old 05-25-12, 05:39 PM   #10
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If you're lucky, it's not a crack, instead it's a void in the lug that didn't get properly filled
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Old 05-25-12, 05:45 PM   #11
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Quote:
Originally Posted by jim p View Post
A frame builder would be what I would consider an expert for the situation.

The other day I had a muffler put on and the guy welded the exhaust pipe. It does not take much to impress me. I was impressed by the way the weld looked. I don't have a clue as to how strong a weld like that would be. Just a thought to be considered.
If a repair is needed, it needs to be brazed by someone who knows how to braze Reynolds tubing. The heat from welding would damage the tubing. Brazing requires less heat.
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Old 05-25-12, 07:09 PM   #12
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Originally Posted by bikepro View Post
If a repair is needed, it needs to be brazed by someone who knows how to braze Reynolds tubing. The heat from welding would damage the tubing. Brazing requires less heat.
+1 if it's a lugged frame, it's almost certainly brazed. Welding would damage or destroy the joint.
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