[ATM] Friction and sticking in multipoint mounts

[artbianconi@blast.net]

A 27 point mount is enormously heavy, regardless of aperture and 
simply not reliable given the technology, the tools used to make 
it and the level of skill needed to fabricate it. 

A famous writer-philosopher once volunteered that if you bite 
into an egg and taste something wrong, it's pointless to keep 
eating it, expecting things to be different. 

To foist such a bad egg on amateurs and create an expectation 
based on book-theory is unfair to them. As proof of this I offer 
you the simple fact that this entire string started as a 
consequence of one person trying to overcome an enormous friction 
problem. How many others are out there whose friction levels are 
beneath the level of human detection but still affecting the 
image?

Other ATM's have volunteered opinions similar to mine and I have 
not even begun to explore the problems that occur when oxidation 
sets it or the binding that will occur when torsional loads are 
imposed and flexing occurs in this complex, interactive system.

I didn't pursue the matter any further with the guys from Bell 
Labs as I was not looking to them for solutions but for 
confirmation of my own estimates.  I took a bite, didn't like it 
so why continue?

My cell will be a super rigid "wheel". one with four layers of 
cored and laminated carbon fiber separated by spokes with an "I" 
beam cross section made the same way.

The 15" mirror will "float" on a thin "liquid like" material and 
be secured with a new breed of polymer developed by NASA. There 
will be no measurable deflection under normal loads and the 
mirror will maintain it's shape. For all practical purposes, this 
will be a super rigid system. 

My 6 inch will employ the same cell technology only I won't 
bother with the thin "liquid like" material interface.

I am not going to defend the design against arm-chair nay sayer's 
and theorists many of which think nothing of making a 1/12 wave 
mirror and then mounting it in plywood or a cardboard tube from 
Home Depot!  It's been tested to death by people at two different 
companies who specialize in far more sophisticated finite element 
analysis than PLOP. They have verified my design and know the 
environment in which it must work. One FEA analyst said it best:

"Art, you did it again. . . . . you over-designed the damn 
thing!" 

It's stronger and has greater deflection resistance than the half 
inch boiler plate steel GEM my 12.5" sits in and that thing 
weighs in at close to half a ton when assembled!

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