Grainer

 An infusion of pigeon's dung used by tanners to neutralize the effects of lime and give flexibility to skins; -- called also grains and bate.  [1913 Webster]

 A knife for taking the hair off skins.  [1913 Webster]

 One who paints in imitation of the grain of wood, marble, etc.; also, the brush or tool used in graining.  [1913 Webster]