Peter Grange wrote:

However, I recently found out what it was. The skewers that hold the
seat in place had oil on them, and the oil had made its way onto the
face of the washers on the skewers which press on the seat mounting to
hold it in place.

Cleaned everything up, back to silent seat again.

In my experience one uses oil to stop squeaks, but in this case it was
causing it.

Any mechanically-minded people out there with an explanation?

A rather vague guess, where you add it to stop squeaks it's to make
movement between parts /easier/. In this case you don't things
moving at all, so making things move more easily could increase
movement from effectively zero to a little bit, which gives rise to
creaks.

But I'm no engineer...

Pete.
--
Peter Clinch Medical Physics IT Officer
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