I want to use tung oil finish on part of my 3-D scroll saw project, and wondered if I could then use a Minwax wood finish on the piece. I used Baltic birch for the project. – Sharon Hill
Tim Inman: I’m not exactly sure why you would want to do this, but it could be done. The very best advice I can offer is this: Always test first on a sample piece. Tung oil finishes are a wide and varied lot. Some are simply tung oil. Other finishes advertised as “tung oil finish” are actually varnishes with some drying tung oil added for effect and for merchandising purposes. So … test to be sure. The issue you’ll be wanting to explore is actually adhesion between the two surfaces. Chemical compatibility between the two is almost a certain “Go” with these materials. Will they bond to each other? When there has been a long time interval between oil and varnish coats, the potential for adhesion troubles increases.
Chris Marshall: Sharon, it sounds like you’re after a nice, clear finish on your Baltic birch project and something that might give the surface veneer some “depth.” I’ve used Zinsser’s SealCoat on Baltic in the past, and I think it produces good effect. It’s just dewaxed shellac. Brush or wipe it on, and it dries very quickly. To me, the shellac seems to mimic the luster of an oil-based finish like tung oil or oil-based varnish, but it won’t impart an amber tone to the plywood. You can find SealCoat at some home centers and hardware stores or, of course, online.