My sister is a beekeeper, or maybe a meta-beekeper. She ends up making more money by breeding and selling new queen bees to other beekeepers than she does by selling honey, but that doesn’t mean that she doesn’t also process the sweet stuff from time to time. She got a free steam-heated oscillating hot knife, used for cutting the waxy caps off of the tops of the cells before spinning the combs down to extract honey, and she thought it might be easier to use than her trusty hand-held electric hot knife.
The oscillating knife, which was built something like a century ago, hadn’t been used in decades. All of the grease had turned to glue, and the large v-belt wheel that made it go was hard to turn by hand, and the motor was missing anyway. So she gave it to my father and me as a project. How could we resist?
We found the original manual on the Internet, which said that it would run from any 1/2 hp motor, or could be optionally driven by a takeoff wheel from a tractor – unfortunately not an option in my sister’s honey house. But we did find a 3/4 hp bench grinder at Harbor Freight that conveniently fit inside the case, and bought the smallest v-belt pulley wheel that would fit the grinder’s arbor. We thought we were geniuses, but when we hooked it all up, it just stalled.
We spent more than a few hours taking the mechanism apart. It was basically an eccentric shaft with a bearing on the end, and the bearing ran back and forth in the groove of a sliding mechanism that the knife blade attached to. As mentioned above, everything was gunked, so we took it all apart. The bearing was seized, so we freed that up by getting the sand out of the balls. The bearing couldn’t move freely in the slide either, but we filed that down until it just moved freely without noticeable play. We added grease from this century, and reassembled it. It turned fine by hand.
But with the belt and motor attached, the mechanism still had just enough friction to stall out the motor. Of course we wrapped some rope around the shaft and pull-started it, and it made a hell of a racket, nearly vibrated itself off the table, and we could see that the marvelous zinc-coated frame that held it all together was racking under the tension. It would require a wholly new housing to be viable, and we hadn’t even figured out a source of steam to heat the knife.
In short, it was more trouble than it was worth. So we packed up the bench grinder in the original container, and returned it no-worse-for-wear to the Freight. But frankly, we had a fantastic time playing around with a noble machine from a long-gone past. We got it “working” even if that state was unworkable, and we were only out the cost of the small v-belt pulley. Who says all of your projects have to be a success to be fun?
