I have a table from the 60s with a shellac finish. I would like to make it water resistant, but don’t want to strip it and lose the current stain. I’m not a big fan of polyurethane, only because it chips over time and cannot be repaired. What do you recommend? Can Tung or Danish oils be applied over shellac?
Both Tung oil and Danish oil are designed to soak into the wood surface so they won't do a good job. A varnish will stick to the shellac and will give you a water resistant surface. Choose a good tried and true varnish, talk to the salesperson at the paint store (a real paint store not a glorified hardware store) for recommendations.