Windshaft

The windshaft is a part in a windmill that carries the sails and also the brake wheel (Smock and Tower mills, and in some Post mills) or the head wheel and tail wheel in a Post Mill. Windshafts can be wholly made of wood, or wood with a cast iron poll end (upon where the sails are mounted) or entirely of cast iron.

brake wheel

crown wheel with cogs

A windshaft lying near a mill

Windshaft connected to other parts. 1=sails; 2=windshaft; 3=brake wheel, 4=crown wheel with cogs; 5=vertical or main shaft.