What is a tailpole?
A tailpole is a large, long beam that slopes down from the back of a windmill to, or just above, the ground or the stage. The miller uses it to turn the cap, or on a post mill the entire mill body, so the sails face squarely into the wind. This is called winding the mill. In Dutch the beam is called a staartbalk.
How a tailpole works
The tailpole is fixed at the top to the rotating cap or body and is supported by braces, so it acts as a lever. At the bottom there is a winch or a wheel. The miller attaches a chain or rope to one of the posts set around the mill and winds it in, which pulls the tailpole and turns the cap with it. Because the beam is long, the leverage is large and one person can move the heavy cap.
You find a tailpole on mills that are winded from outside, such as the post mill and many smock and tower mills without a fantail. Mills with internal winding gear or a fantail turn the cap differently and have no tailpole.
Application
- Identify the type. A tailpole on the outside immediately tells you the mill is winded by hand from outside.
- Watch the lower end. Where the tailpole comes close to the ground, moisture lingers. Rot often starts at the bottom and at the joints with the braces.
- Check the joints. Loose or split joints between tailpole, braces and cap make winding heavy and unsafe.
- Leave repairs to a millwright. The tailpole is structurally important. Most mills are listed buildings, so agree any replacement with the owner and the heritage authority first.
Common mistake: propping up a rotten tailpole with loose steel straps. The forces during winding are high; a weakened tailpole can snap without warning.
Related terms
- Windmill
- Brace
- Listed building
- Restoration
- Wood rot
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