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Old August 1st 03, 02:21 AM
Peter Dohm
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Corrie wrote:

john wrote in message . ..
On 30 Jul 2003 16:56:37 -0700, (Corrie) wrote:


"MS20001P aluminum hinge is extruded. The closed hinge loops cannot be
pulled apart. Furnished with hinge pin. Anodized finish."


Thanks. How much stress can it take, though? That's the question.
Probably the hinge pin or the rivets holding the plates would be the
first to fail at a few hundred pounds, but still... musing I
suppose one could order some and find out.... If the specific alloy
were known, it could be looked up.
http://ourworld.compuserve.com/homep...orhis/T003.htm shows
yield and tensile strengths for a number of allows. They tend to be
around 30kpsi. The catalog doesn't give the thickness of the flange.
Assume it's .1", and the hinge is 6" long, that's .6 sq. in, at
30kpsi.. 18,000 lbs? But some alloys are as low as 5kpsi - that's
3,000 lbs. Impressive for a small hinge, but would it suffice for the
application? Marginal at best, I think.

The largest hinge at AS&S is just 2" wide, and they all seem to have
the same size pin - .089 stainless. That's .006 sq. in. area. I
can't find a reference for shear strength for stainless, but taking an
optimistic SWAG at 200kpsi (the highest yield strength for drawn ss
referenced at http://ourworld.compuserve.com/homep...orhis/T006.htm),
that's 200,000 x .006 = 1200 lbs. Not nearly good enough. /musing

My guess is that if it's not specifically rated and labeled, it's
unknown. Not something to put in a critical area. So, then, back to
the original question. Assuming you don't have the ability to extrude
a larger piece of aluminum (in order to use a larger pin), how *do*
you solve the problem?



I really feel like a big dummy, because I may have missed the obvious,
and I know that I may have nothing usefull to add after all ... but ...

What are these hinges supposed to hold???
pressurized canopy?
undercarriage trunion?
control surface?
some kind of single hinge application?

Peter