I would follow up the varnish oil with several coats of a fine paste wax, the first coat applied with a very fine steel wool gently rubbed. Buff, re-appply, etc.

For the shellac, if you haven't applied it yet, start with several thinned coats (I think alcohol as a thinner).

The more you can get the finish to permeate the wood the better. The wax seals it in and can be freshened up at regular intervals.

Post a few pics when you're done.