This week’s question comes from Eric in Canada who asks: “I know you like to use dewaxed shellac and transtint for a bit of colour, and finish it off with General Finishes. GF is extremely hard to find here in Canada. Dewaxed shellac and the transtint is pretty easy to get. I was wondering if I can use Danish oil on top of the shellac?”
And here was my response:
The only problem with Danish oil in this application is the fact that most Danish oil contains a high amount of oil. That oil will have difficulty curing on top of a pre-sealed surface (from the shellac). The General Finishes products are mostly varnish, if not all varnish (Arm-R-Seal). So what you are really looking for is a simple wipe-on varnish to put over top of the shellac. Minwax sells a decent one that is widely available. A few light coats should do the trick.
You might also consider using a different coloring agent. Even though I do occasionally use a dilute shellac/dye solution for coloring, its only for certain situations. In most cases, I do my staining with water-based dyes or gel stains. Neither of these really seals the surface and you should have no problem following up with a Danish oil if you use them. So really, the sky is the limit for your combinations of coloring agents and topcoats. But to directly answer your question, you want to avoid putting oil/varnish blends on top of sealed surfaces.