Field of raked hay. After two to three days of drying, the mowed hay is raked into a double windrow, meaning two are merged into one, resulting in less time baling. The hay continues to dry as the hay which was underneath is now exposed to the air and sunshine.
The picture below is of our wheel rake. Each arm of wheels moves up and down hydraulically. When the wheels are down, they turn along the ground moving the hay into the center.
Photo by Melissa.
Curiousfarmer 
I have the impression of organization, geometry . . .
What happens when this wheel rake malfunctions or breaks down?
How does it get repaired? Does the curious/good farmer repair all of his farm machinery? Or?
What do the Amish do?
We repair what we can, and know people who will fix what we can’t. The Amish either use ground-driven implements pulled by horses or an implement powered by a motor, still pulled by horses. They don’t use tractors.