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Here's an older project, from back whem monitors were smaller and connections slower. :)
Family friend shows up with the bottom half of what he says was a $1,200 leather office chair. He was ready to throw the thing out,
since the swivel had worn out to the point the chair would sway two or three inches. Before that drastic measure, he decided to
swing it by here, since he's seen some of the magic that's been done over the years.



Problem: Though the rest of the chair is well-built, the pivot is simply a central "pipe" to which are welded five legs,
which are then covered with wood. Inside this pipe is nothing more than a thin plastic sleeve, possibly Delrin.
The shaft that holds the chair up is just a big chunk of ACME-threaded rod that slides down in the plastic sleeve,
with a thin washer at the top (of the sleeve) that takes the downward pressure.

Well, that washer had nothing more than two little tiny spotwelds, which eventually broke and allowed more wobble than usual.
The wobble wore out the Delrin, and then it was metal-on-metal. I looked at it, let my subconscious chew on it for a
few days, then, bright and early this morning I started first with a big 'ol rusty chunk of 1.5" allthread from the scrap heap.





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