Jim Stewart wrote:
John Doe wrote:
Something thin to put between two pieces of 1/8" thick 1 1/2" wide
aluminum flat bar that are bolted together. A bearing that will
allow the two pieces of aluminum flat bar to be held firmly together.
but move (the only way possible) against the spacer between them
with as little friction as possible.

Would that be nylon? Delrin? What is it called? At the moment, my
best guess is "thrust bearing". Even though the only thrust pushing
the pieces together is the bolt that holds them together. I'm
looking at McMaster.

It would be a linear thrust bearing as far
as I can see. Without getting crazy expensive
I'd use nylon or teflon. I know M-C has some
nice thin teflon sheet that you could just
cut out and lay in. If you have more than
a small amount of force, most plastic will
tend to squash down and extrude out. I think
teflon will be better than nylon in that regard

teflon flows much more than nylon. Polyethylene or one of the higher
density ones might be good to try.