Soft coatings are the work of the devil.
Polyurethane in general is the work of the devil.
@mattias does "linseed oil is fairly nice" make sense in that context?

@jnbhlr That's a different application - PUR soft coatings are used to make cheap plastic feel more valuable.

But yes, boiled linseed or a bit more modern. Oil paintings have some charm. Unfortunately even #Owatrol Marine with curing aids takes nearly two weeks to fully cure.

@mattias I love (boiled) linseed oil as I just don't have to worry about what's in it and it's local. However I would like to find an alternative that turns out brighter...
@jnbhlr On rusted steel, I'd try Owatrol Rustol (it's the favorite of the Rat Rot scene), on aluminum Owatrol Marine Oil. The gray GT is just sand blasted and covered with Owatrol Marine Oil. https://mattias.bike/2022/dad-and-daughter-flatbar-gravel/
Dad and daughter flatbar gravel – Mattias' Bike Stuff