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Old 07-18-11, 07:42 PM   #1
nstarrider
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Frame Welding Advice?

I have a 16 year old cro-moly MTB frame with a break between the chain stay and rear dropout. Is it worth having this welded? I have lots of history with this bike and hate to give it up, but don't know if a fix is worth it. is the break is a sign the frame has reached it's useful life? Fix it, or strip the components and look for a new bike? Any advice appreciated.
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Old 07-18-11, 07:46 PM   #2
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Is it the dropout brazing in to the that has weakened
or has the tubing itself cracked?

a few pictures, as usual, will help.
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Old 07-18-11, 09:17 PM   #3
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No easy answer. Id depends if the frame was brazed or welded. What exactly broke, the tube, dropout or the joint.

It's common tom rebraze road frames, even to replace tubes, but it isn't cheap. For a mtb frame with 16 years, I'd lean more toward scrapping it, unless it was a very valuable frame that justifies trying to save.
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Old 07-18-11, 09:38 PM   #4
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I am no expert on these matters but I would fix it. If the weld holds, good. If the weld fails, nothing has been lost. Nobody died the first time it broke so if it breaks again the body count should not increase.
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Old 07-18-11, 09:49 PM   #5
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I am no expert on these matters but I would fix it. If the weld holds, good. If the weld fails, nothing has been lost. Nobody died the first time it broke so if it breaks again the body count should not increase.
That's probably how I'd approach it if I were welding or brazing it myself.

But having this kind of repair done can be pricey, so he may not want to throw good dough away for a short term repair. It does make sense to see someone who might repair it and get his expert opinion, along with an estimate.

Then it's a dollar decision. For small dollars, maybe go for it, for bigger dollars it may not make sense.
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Old 07-18-11, 10:27 PM   #6
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Originally Posted by FBinNY View Post
That's probably how I'd approach it if I were welding or brazing it myself.

But having this kind of repair done can be pricey, so he may not want to throw good dough away for a short term repair. It does make sense to see someone who might repair it and get his expert opinion, along with an estimate.

Then it's a dollar decision. For small dollars, maybe go for it, for bigger dollars it may not make sense.
Good point.
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Old 07-19-11, 12:38 AM   #7
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I had two frames crack on the right chain stay, right near the BB, but just aft of the chainstay bridge. The breakage was along the inner circumference of the stay. Unfortunately, both occurred too close to the bridge, and they were in a critical area where the tire rolls through and if you need "mud" room, any type of reinforcement would basically reduce the clearance. Not sure if yours was the same, but we couldn't think of any cost effective ways to save the joint.

However, if the crack had been just half an inch more aft of the chainstay bridge, we could have brazed a steel sleeve over the break with a long, dagger-shaped tongue that would also be brazed on the exterior of the chainstay, but facing inward toward the spokes.
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Old 08-09-11, 07:32 PM   #8
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Just to follow up with my experience... I found a local frame builder who was able to repair it (welded the break and added a triangular brace for reinforcement). I've put 150 miles on since the repair with no problems. The $75 he charged seems well worth it.
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