Re: [ATM] Help with Strut Flexure in my 3 Truss DOB

[Daniel Fundo <fundo@bellsouth.net>]

<<  As I understand it from the original message, there are only three 
(nearly parallel) tubes supporting the upper cage, instead of three 
PAIRS of poles.  Is this correct?

If it is correct, then the problem is that the current "trusses" are 
not actually trusses, they are simply cantilevered beams.  If they are 
indeed 1.25" in diameter, then it's no wonder they are flexing over 
that length.  >>

As Mel pointed out, with just three poles, the connection points on at
least one end have to be fixed and rigid.  It would be better if both
ends had rigid connections.  By rigid, I mean not able to translate in
any direction about the joint.  The best way to do this is to pass the
member through two or more holes, as the Highe design does.

*****-----
Dan F.
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