: As Malcolm says, if you are adding epoxy, you really want to get
: rid of the old varnish.
: I'd be inclined to use a good chemical stripper; I hate sanding
: varnish/paint.
: If there was still some texture showing from the fabric weave, a
: scrub brush can help.

: Make sure you get the stripper rinsed off before you epoxy.

Agree completely, not only will the chemical stripper remove the varnish much more easily it won't remove the epoxy which is awfully easy when sanding. Very hard to tell when you're sanding what's varnish and what's epoxy and if you sand into the weave of the glass it'll never be completely clear again, will always have some silver colored flecks in the finish.

Bill H.