To "restore" the finish on your table use denatured alcohol and rags. Pour the denatured alcohol on the rag and then wipe with the grain in long quick strokes. This dissolves the old scratched shellac, spreading it to fill in the scratches. All you're doing is redistributing the finish! Let dry,then wax with a very good furniture grade wax. Your table will look beautiful and best of all, the same as when it was new.
I did this with the table top on my Singer 15-91 a month ago. It's so beautiful now!
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