> You can make a useful dull black spirit varnish by dissolving
> an old shellac 78 rpm record in denatured alcohol.

But please make sure that the record you dissolve isn't a rare one.
Most anything from the mid 1940s on Bullet, RCA Victor or Decca would
be a good choice, in my opinion.  Don't use Columbia discs as they have
a cardboard laminate and will make a horrible mess when dissolved.

Not that they don't have good music on them, but the world abounds in
them.

Sincerely,
Bob Hodge