What to do with the #paint on a door like this? Strip it off back to bare timber. For a translucent finish to highlight the grain, while maintaining the current colour, use oxalic acid to remove the stains, and finish with tinted hardwax oil from Osmo. If the woodwork turns out to be ropy, which is often the case for painted doors, the quick answer is a solid finish again with primer, undercoats and top coats. For super flat finish check out gras à lacquer linseed oil filler. The secret to. 10 Downing St door before it was bombproof metal.