Recently I tried somethingon my garden beds I used on my hammers for a few years, basically I burned the wood, scrapped off the excess char, rubbed on a coat of boiled linseed oil, burned it again and repeated 2 or 3 times. I was told that was how they made the black stave churches in Europe but have looked into it and it's not quite what they did. It leaves the wood black obviously but it lasts longer than paint( I'm not planning to touch it again for 5 years and even then likely won't replace anything), and looks way nicer in my opinion.