July 14, 2022
I was attending the University of Cincinnati in the college of engineering. After my freshman year in 1960, I started my co-op job with the Cincinnati Gear Company. The two founding partners had been working for a Philadelphia gear company and had saved enough money to buy two bevel gear cutting machines. Since they knew that a lot of the gears that their employer was making were being shipped to Cincinnati, they had their machines shipped to Cincinnati. The Cincinnati Gear Company became a complete gear company — making bevel gears, external and internal parallel shaft gears, worm gears, and racks. They made the gears to the customers’ prints; they even made a couple of gear assemblies to the customers’ designs. The owners were concerned whether they could keep the plant busy after the war, so the factory was designed so that it could be converted into a bowling alley if necessary. The engineering department was mainly a methods department, where they routed the production of the parts through the shop from cut off of bar stock or purchased forgings, turning, cutting, finishing if necessary, and outside heat treating. They had inspection machines that independently measured the lead, profile, and spacing. As a co-op student you would spend one section — seven weeks — on the job and then seven weeks in school. There would be an alternate co-op working when you were in school. This schedule would continue for three years. You would then attend school for the final year of your five year program. My first work section was in the shop as a machinist assistant setting up and producing pump gear blanks on an Acme Gridley four-bar feed machine. We made thousands of these blanks. I learned to use micrometers to measure the outside diameters and face widths, depth mics to measure the hub lengths, and bore gages to measure the size in the bore. My next job was assisting in setting up and manufacturing bevel gear blanks on a Cleveland automatic screw machine. Here, we made the blanks from a single bar stock fed automatically into the screw machine. Here I learned how to measure the face and back angles on the blanks. I worked in various shop departments — cut off saws; turning; hobbing; shaping; shaving; burring; shaft grinding; bore grinding; milling machine; and inspection. When we got to the gear company, the VP of engineering knew a lot about gearing from prior experience; his father had been an earlier shop superintendent at Cincinnati Gear. The VP did not have an engineering degree, but had enough experience to help customers design the gears and direct the methods people to produce them. After about two years in the shop, I went into the office as an assistant to the VP of engineering. I calculated the set-up for the gear inspection machines using a Friden mechanical calculator. We used mathematic tables in an Illinois Tool small booklet for the trigonometric and involute functions. I also calculated the sizes over pins for the gear measurements; these calculations were also done on the Friden calculator. We did not see an electronic calculator until after we graduated from college. During my final year of co-op working, I designed a gearbox that reduced the speed of a hydraulic motor that used pump gears in the motor. This included designing the housing, selecting the bearings and seals, and testing the assembly. The unit was a vertical design with splash lubrication. This design work was mostly self-taught, using the reference books that were in the office of the VP of engineering. In school, the machine design class included one chapter on gear design in the M. F. Spotts book. About this time I was introduced to the red cover Maag Gear Book. We also got a copy of the Gear Handbook, edited by Darle Dudley. Another good gear reference was Practical Gear Design, also by Dudley. By the time we graduated with a BSME, the gear company had signed a license to manufacture epicyclic gearing designs that included an arrangement to have equal load sharing on the planet gears. The gentleman who held the patent on the epicyclic gear design visited our plant several times and introduced us to x-factor [rack offset] gearing. He liked to use x = .5 for the sun pinion and planet gears and x = 1.5 on the internal gear. All of his designs were 25° pressure angle, and this gave him a higher operating pressure angle than 20°. This also gave him stronger teeth. We were starting to use 25° pressure angles for increased strength and avoided undercut on the involute. While at UC, I joined the student section of ASME. I ended up being a 40-year lifetime member of ASME. I graduated with a BSME degree in 1964 and joined Cincinnati Gear full time as a project engineer. At the urging of a colleague, I decided to continue my education at night school. When we took the advanced machine design class, the teacher actually had us teach the section on gear design. It was in the Master’s program that we were introduced to computers. My work included the design, assembly, and testing of the various designs. I was encouraged to participate in several AGMA committees. I authored the article introducing the “modern” AGMA gear rating standard to the world that was published in Machine Design magazine. My participation in various AGMA committee meetings allowed me to learn a lot and to meet some well-known gear designers I retired from the Cincinnati Gear Company in 2001 as — ironically enough — VP of engineering. Since that time, I have been active as a gear consultant.