Last night I was designing a gearbox, but I couldn't get the ratios correctly with the current dog gears available. At one point, I did manage to find a good ratio, but it turned out later that parts were intersecting. This prompted me to find a decent way to somehow work around this without too much machine work. Since the PTO Hub from VexPro converts anything with a versakey to essentially a dog gear (or sprocket), I figured that this could allow me to have "dog gears" aside from the ones manufactured by Andymark or VexPro. For instance, I can have a 72T gear with a 1.125in bearing pocket, and use the PTO hub to get a decent low gear speed in a transmission gearboxes.
Here's a small proof of concept:

Note that with this setup, the gear's bearing pocket had to be widened for the bearing that goes into the PTO hub. It might not be the best way to mount it (moving the gear to the other side saves space, but the distance between the two gears becomes too small for the gears on different shaft).
Anyways, this thread is here because I'm not sure if the PTO hub is designed for such applications and I would like to confirm that this could actually work, and also because with this people may be able to design gearboxes using better ratios (Not entirely sure, but hopefully

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