Engineering Question: How much overlap for 2 steel tubes to develop max strength?

[x]

If we have two steel tubes (as in a seatpost and a down tube) and slide one inside the other; how
much overlap is needed before maximum strength is attained? I'm guessing it has something to do with
the diameter of one of the tubes...
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Pete Cresswell

 

[Scic]

>From: "(Pete Cresswell)" [email protected]

>If we have two steel tubes...

I seem to recall the minimum insertion point to be 4X the OD of the smaller tube, but don't ask me
where it was read/heard/learned because I don't know.

Sig Chicago

 

[Phil Holman]

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