This is a round wheel, with dowels sticking out from it, around the perimeter, much like candles on a birthday cake. The water wheel’s axle will often have a crown wheel attached to the other end. The other exception that exists with wood gears is something specific to water wheels. This is actually quite common, especially when using gears and sprockets together. In that case, one gear can be toothed to work with one set and the other can have a different size and/or type of tooth to work with another set. One exception is where two gears are mounted on the same shaft, turning together. In each case, the teeth on every gear used in the set have to match. It doesn’t matter if we’re talking about spur gears, internal gears, helical gears or bevel gears. The second thing we need to understand is that for any set of gears to work requires all the teeth of the gear to be the same size and shape. The basic difference is that gears are designed to mesh with other gears, while sprockets are designed to be used with chains or toothed belts. To start with, the terms “gear” and “sprocket” are often used interchangeably, even though they aren’t the same thing. There’s a fair amount of misunderstanding about gears that we should probably clear up, before getting into making any gears. The idea of making wood gears isn’t just to get the finished gears, but also to enjoy the road from here to there. While that works well and produces clean gears easily, it takes something enjoyable and challenging out of the process.
By “cheat” I’m referring to making them via laser cutting. Many people who make these gears cheat a bit, just like the companies who manufacture wood gears for sale.
It all depends on the woodworker’s imagination. There exists a wide range of ways that wood gears can be used for making that tooling, such as in moving a sliding table. That doesn’t mean that they have to be limited to that use though, as they can be quite useful for those of us who make our own jigs and power tools. Woodworkers People make wood gears more for decorative purposes, than anything else. Today, wood gears are more of a novelty than anything else. The constant wear on the wood demonstrated the need to switch over to metal, providing more accuracy and durability. Many early clocks used wood gears as well, although few examples remain to us today. We normally only see the wheel itself, but the wheel rotates around an axle (a whole tree trunk), that goes into the lower room of the mill, where it is run through a right-angle gear drive, and possibly other gears to increase the speed, allowing the power developed to be sent upstairs into the working area of the mill. One of the more prolific uses of wood gears was in conjunction with water wheels. While some of those early gears may have been made of metal, there were also a lot of gears made of wood.
Due to the lack of reliable communications and commercialization, inventions didn’t spread as rapidly as they do today. Of course, like many ancient inventions, neither of these preclude the other, as there were many inventions that came about in different places at different times.
There is other evidence pointing to the Chinese as the actual inventors, who may have used gears in chariots centuries before that. But there is evidence that they were used by the Greeks in the third century BC, having been invented by Archimedes. While the actual history of early gears is rather unclear, they were first written about by the Greek mathematician Hero of Alexandria in 50 AD. Wooden gears and sprockets have been in use for millennia.