Riley and Son Ltd: Locomotive Engineers

Where I worked in ironstone quarries we had special paint for smokeboxes ,they used to call it black jack ,it was very thick ,it would never run of the brush ,it could nearly be put on with a scraper. After one loco had had a major overhaul some bright spark painted the ash pan with it ,the effect was to make the loco men eyes smart for several days.
With smoke boxes its best not to get them hot in the first place, the two engines that worked up to the main line sidings ,maybe half a mile at 1in 35/40{no gradient post just a guess )had all the gaps around the steam pipes, in the smokebox, filled with concrete, a plate probably 3/8 inch thick, half the size of the smokebox door placed just in side. Clips around outside the door as well as the dart in the middle. All that kept the door just about cool ,never hot.