My Grandson and I are building a 90 degree jack shaft as a winter project .....it works out as a good way to teach him about gears and ratios etc.

In the process I came across a couple of videos I thought some of you might get a kick out of. I must have led a shelter life as I have never seen square gears before!!!!!

Hit and miss square gear can crusher - YouTube

While that was interesting, this is the darnedest set of gears I've ever seen, especially considering they were actually manufactured and sold!!!!!


Kuhlman Pump Jack Hit Miss Engine Display 2013 - YouTube


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