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Welding of cantilever pivot

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Welding of cantilever pivot

Old 04-27-18, 05:52 PM
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reueladhikari
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Welding of cantilever pivot

Hi Everyone, perhaps being too picky here, but have a look at the welding of this canti pivot. The pics are from the wheel side of right fork leg. There appears to be less brazing material on one side and a tiny gap. Should this be OK safety wise?
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Old 04-27-18, 06:04 PM
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79pmooney
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I'm not an expert. The first thing I would do is take it to a framebuilder and get his opinion. Of course that's easy for me to say; what with 30+ in the immediate area for me to chose from and one of those knows me well, knows my riding and has enough work he doesn't need the job.

Ben
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Old 04-27-18, 08:31 PM
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Looks fine to me if the remainder of the boss(that which we can't see) is adequately brazed. Not all bosses are designed for continuous brazing along the boss base, such as the one on the right below.

regards, Brian

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Old 04-27-18, 10:44 PM
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Brian makes a good point. But to continue it- What you want is enough surface area joined, between the boss and the blade, around the base to spread out the forces and reduce the leverage that the braking forces have on the base's joining. Without seeing the entire boss base joining we can't really say much.

I will say that steel tends to fail slowly with a lot of warning if looked for. I have seen what looked to be far worse boss/blade joinings (welds or brazings) that have been many miles old with no issues. The number of broken bosses (and I don't mean the shaft like in another recent thread here) are very few in real life. Andy
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Old 04-28-18, 07:13 AM
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reueladhikari
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The canti bosses are more like the left one on Brian's pic above. Here are the views from below and opposite side. I suppose this isn't much of a flaw then.
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Old 04-28-18, 03:07 PM
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If you add a brake booster arch on , after sliding the brake on the post.
the force on the end of that post will be shared with the arch..
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Old 05-01-18, 09:56 AM
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it looks fine to me. I probably would have flowed more brass in the one side just to make it look better. Is this a production frame?
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Old 05-03-18, 06:06 AM
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Got a horseshoe brake booster here. I plan to use it if there is significant squealing. It is a sort of a production frame: Gunnar Crosshairs
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