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Re: Bronze (One-legged Support) Horse Structure

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I don't think that a higher strength material will necessarily solve all
your problems.

I did some research on various steel alloys for a land speed record vehicle
tubular frame, where lighter is definitely better. The higher strength
materials provide a higher yield point, but contribute little to the
stiffness of the structure. There is no substitute for basic section
properties. None of the steel materials I could find would allow a reduction
in tube diameter, and therefore shell size and air drag, without far greater
negative performance and stability effects.

Have you looked at the deflection of the sculpture? Assuming a fixed length
between center point of attachment and point of fixity, and a constant
moment, the deflection is dependent on only E and I.

My experience is that stainless tends to have a slightly lower E than
typical structural steels, and the drop from 2" dia. to 1.25" dia. reduces
the I value by approx. 85%.

Another issue to consider is the torsional effects of a good cross wind. The
same 85% reduction in rigidity applies.

IMHO, if the larger bar fits, you're better off.

Paul Feather, P.E.