(meandering a bit off topic)
Quote:
Originally Posted by AdamHeard
Modeling a round tube conservatively at .5x.201 I get 97.4% the bending stength.
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For those curious why the hole makes little difference to the bending strength, check out the list of
second moment area of inertias for different shapes. For two axles of the same diameter, the second moment area of inertia is proportional to the amount of bending load it can withstand. The r^4 term is what makes the small hole have little effect on the bending strength of the axle.
My napkin calculations put the ThunderHex axle (with the hole) at about 46% stronger (in bending) than a solid 7/16" hex shaft of the same material.