Puckdropper wrote:
....

I didn't think about the finishes. It makes sense, though. After seeing
how fast some of the sand paper gummed up cleaning polyurethane, I'd hate
to have something similiar happen to the knives.
....

Other than heavy coats of enamel or other hard finishes it'll make
little difference--varnishes, etc., are much softer than the wood itself
and don't abrade the surface to create heat, etc., in the way the
friction of sandpaper does.

That said, large volumes of surfaced material will make some difference
but other than the old paint, not so much as to be such a major issue.

But, as a matter of course, if I have old material to clean up (and I
reuse a tremendous amount of recycled/reclaimed material) I keep an old
set of knives for the purpose as opposed to a finish set for fine work.

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