When I acquired this boat in 1962 the masts were painted. Eventually rot set into the top of the main adjacent to a fastening. The paint had done a nice job of masking it. After scarfing on a new top section I have kept it varnished, which makes it far easier to detect the onset of problems. Yes, paint lasts longer, and I don't enjoy varnishing, but it's safer and they look a lot better.
Years ago an old timer came by while I was docked in Gloucester, and chastized me for having painted masts. When I told him that I already had more maintenance than I could handle he said, "Just slush 'em down with used motor oil like we did on the fishing schooners."
When it comes to varnish, I have had the best luck with Pettit's Flagship. I stripped them and put on six coats four years ago. And as I speak, we are doing it again.
Anyone have a better idea?
Never sail closer to the wind in degrees than your age