Originally Posted by Mister_Lee:
Another reason why steam locomotives were painted black was because for a long time, nobody could make paint that could stand up to the smokeboxes' hot temperatures. Eventualy somebody developed an aluminum-like color that could, but some railroads stuck with black or a very dark gray until the bitter end.
Actually, that "dark gray" on smoke boxes and firebox sides, was usually a mixture of valve oil or Linseed oil and powered graphite. On most railroads, neither the smoke box nor the firebox sides were insulated, so SOMETHING was needed to cover them that would NOT burn off quickly do to the direct heat.
