I have a recepe for spar varnish, tung oil, pure turpentine and japanese dryer. It was put on a gun stock using 200 grit and letting the excess dust oil up and fill the pores. The same was repeated with 350 grit. Then it was finished using 600 grit. That was 30 years ago. I have heavily used the gun for moose and elk and it has many marks on the stock. But the finish has stood up, not peeled or brushed off and it hasn't turned any noticeable yellow. I also had this finish applied to a trap gun at the same time and I have never had to touch up the finish in all those years.
