Dust Floor / Cap @museum.de

And here we are! Our mill is one of the very few where you can climb all the way to the top, just under the cap. For safety reasons, visitors aren’t allowed to climb into the cap itself.

Here on the dust floor, the mystery of the sack hoist is solved. Do you see the spindle with a rope running over it? That spindle is connected via a wooden axle to a toothless wheel, which is powered by the slowly rotating upright shaft. As the spindle starts moving, it hauls the heavy sacks of grain up to the stone floor with energy to spare.

From here, there’s a great view all the way up into the cap. If you focus on the area of daylight, you can see how the windmill sails are connected to the upright shaft via the wind shaft and the brake wheel. The wind energy is what powers the upright shaft.

The wind shaft is supported by a stone bearing. In German, it’s called the “Katzenstein”, or cat stone; in English, it’s the neck bearing. It’s usually made of granite. Take a look at your screen to see what it looks like. On the wind shaft sits a wooden box with a lid. The box contains a chunk of beef tallow that continually lubricates both the shaft and the neck bearing. If you’re wondering about the German name cat stone – it seems an unlubricated wind shaft gives off an unfortunate smell – of cat pee.

You’ll see a gear rim. That’s the winding gear that runs around the inside of the entire cap. It is part of the fantail’s chain mechanism. The fantail itself sits outside on the cap.

It rotates and drives a small gear wheel in the cap, and that in turn sets the worm drive in motion via chains and other gears. So every time the wind direction changes, the fantail activates the worm drive and slowly turns the cap into the wind along with the sweep.