This is a Victorian dresser that came in to be restored, luckily it had it’s original shellac finish so it could be repaired and not refinished. One of the advantages of shellac and lacquer is that they can be re-amalgamated.
The first thing I did was to very lightly scrape the top with a card scraper to remove any loose finish and big chunks of debris.
There was a large chip missing from the back corner of the top.
I planed the corner in preparation for a patch.
The patch glued in place.
The patch shaped and sanded.
The top had black water and iron stains.
The stains were bleached and scrubbed with oxalic acid. Actually what’s in the jar is oxalic acid based deck wash.
The top after bleaching and washing with TSP.
Next what remained of the finish was re-amalgamated with denatured alcohol. Basically the old shellac is dissolved with the alcohol and a brush and then brushed out to cover the surface. You are covering the entire top with what finish is left. On a piece with less severe damage this can be done without the need for further repair.
The entire top re-amalgamated.
A coat of toner to bring back the color.
The top polished.
Finished.
millcreek woodworking 
Whoa! This was a wonderfully timely post. We have a pair of nightstands that my wife’s grandfather made that need attention. Some of the brown shellac is a has flaked off the tops and the chip carved drawer fronts. I thought I would need to strip them completely. Thanks!
Great job repairing and refinishing the top!
Chris
Thanks. I have a very old side table with some flaked shellac. I was thinking about removing it all and putting an all new coat of shellac on it. I’ll try this first.