Building Windmills with Windmill Bearings and Sails for Rotational Force
A windmill in Create is a player-built structure that turns Sails into a source of Rotational Force, using a 
Windmill Bearing as the core block that spins the whole assembly. The bearing does not generate force on its own — it needs a movable structure attached to it, and that structure needs enough sail-like blocks to act as a windmill.
Placing the Windmill Bearing
The Windmill Bearing attaches to the block directly in front of it. Keep that attachment point in mind before you build, since the structure it drives has to sit on the correct side of the bearing. Once the bearing is placed and connected, you are ready to construct the rotating part.
Building the Rotating Structure
Build a movable structure and hold it together with 
Super Glue. Gluing is what keeps the separate blocks acting as one unit when the bearing starts turning, so an unglued build will not hold together as a windmill.
Include enough sail-like blocks in that structure. If enough Sail-like blocks are included, the assembly can act as a Windmill. The number of Sail blocks you use determines the rotation speed of the finished windmill, so a larger sail area spins faster.
Assembling with Sails
Sails are handy blocks to create windmills with, and they simplify the build considerably. They attach to blocks and to each other without the need for Super Glue or Chassis Blocks, so you can lay out a sail surface directly rather than gluing every piece.
Sails can also be customized:
- Right-click with Dye to paint them.
- Right-click with Shears to turn them back into frames.
Activating and Controlling the Bearing
Activate the Windmill Bearing with Right-Click, and it will start providing Rotational Force. Use the value panel on the bearing to configure its rotation direction. If you need to change the structure, Right-click the Bearing anytime to stop it and edit the Structure again.
Other Ways to Generate Rotational Force
Windmills are not the only option for producing force. Water Wheels and Large Water Wheels both draw force from adjacent Water Currents. For either type, covering additional sides will not improve its kinetic output further, so there is no benefit to enclosing more of the wheel in water.
A Large Water Wheel rotates only at half the speed of a regular water wheel, but it provides a substantially higher stress capacity. Both wheel types accept wood planks on the wheel to change its appearance, letting you match them to the rest of your build.
Choosing Between Them
Reach for a windmill when you want a compact, vertical force source whose speed scales with the number of Sails you include, and reach for water wheels when you have a current available and want a simpler footprint. Whichever you pick, the same principle applies: the structure supplies the motion, and the bearing or wheel converts it into Rotational Force you can route into the rest of your contraption.
Covers the mod’s in-game guide topics: Generating Rotational Force using Windmill Bearings Assembling Windmills using Sails Generating Rotational Force using Large Water Wheels Generating Rotational Force using Water Wheels