Thread: #25 Chain
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Unread 06-03-2016, 11:03
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Re: #25 Chain

Quote:
Originally Posted by Ether View Post
I'm understanding you to say the failure mode is external impact damage to the cotter pin. It's not wear or normal shock loads or fatigue failure. Is that correct?


The cotter pin is part of it, but the link is just not as strong.

The zig-zag plates in an "offset link" are set up to have complex loads on them (unlike standard links that have plates that are in very simple tension loads by design - assuming your chain sprockets are aligned properly). Anything you can do to help support that load is going to make the chain stronger.

With the cotter pin type offset link, the pin is a slip fit (the pin that carries the load, not the cotter pin). This type of joint gives less support to the zig-zap plate than in the other type of offset link, where the pin is smashed/mushroomed so that the pin and the plates are more effectively joined. Again, that better joint between the pin and the zig-zag plate translates to a stronger offset link.

And this is completely separate than from the whole cotter pins are subject to mis-application when they are so small and jewelry like.

Dr. Joe J.
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Last edited by Joe Johnson : 06-03-2016 at 16:48.
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