Bob LaCivita replies: When making the classic oil varnish finish, I use polymerized tung oil, turpentine and varnish—1/3 of each ingredient. Raw tung oil drys very slow or not at all. I use a varnish with the highest amount of solids that I can find. Parks and Sherwin Williams both make a high solid varnish. I know of nothing that will dry a tacky finish. I would suggest that you sand the piece down to bare wood and start over.