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On Friday, 17 January 2020 02:47:30 UTC, Bill Wright wrote:
I was trying to think of all the sacrificial things. Sacrificial anodes
on ships, yes. But... how about the face of a wooden mallet? Because the
reason it's wood is because steel would be too hard. Because the wood is
softer it's more likely to get damaged. Stretching a point? A wooden
gramophone needle, which wears out quickly but doesn't damage the
shellac? Can anyone think of sacrificial things?

gram needles were often thorns.

Well I never knew that. How did they attach the thorn to the sensing device
(diaphragm of mechanical horn, moving iron in coil, or piezo crystal)
sufficiently firmly that no frequencies were attenuated by the flexibility
of the thorn and of the thorn-to-sensor joint and yet which allowed the
thorn to be replaced quickly and easily whenever it wore down?

Interesting that "modern" (well, before LPs were supplanted by CDs etc) was
the exact opposite philosophy: stylus made of diamond which is extremely
hard, and which could theoretically damage the vinyl record.