On Tue, 04 Oct 2011 20:07:53 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

"Nok" fired this volley in
:

Hi All,
I'm building an aluminum hinged cover for a dry well. The hinge
barrels are 1" o.d. aluminim and I had originally planned on stainless
hinge pins. Any reason not to use aluminum hinge pins (much cheaper)?
Thanks,
Nok


There are a few: First, aluminum on aluminum tends to gall. If nothing
else, this will make the hinge "creaky" and hard to work.

Second, unless you specify exactly the same alloy from the same source
for the hinge tubes and the pins, you'll get dissimilar metals corrosion
in the joints. That tends not to happen with stainless-on-aluminum
(although they are dissimilar metals, also).

Third, mill-finish aluminum tends to easily corrode upon exposure to the
elements. SS hinge pins will at least keep the running surfaces
"polished" instead of pitting (together) and becoming hard to move.

In any case, keep them protected from the elements, well-lubricated, and
moved often.

LLoyd

What Lloyd said. Here is a useful table of some typical coefficients
of friction:

http://www.engineershandbook.com/Tab...efficients.htm

Aluminum on aluminum is quite high.
--
Best -- Terry