October 12, 2022
Blogging from an American perspective can sometimes make me forget that the gear industry is active around the world. I get occasional reminders in the form of e-mail questions from engineers or students in other countries. Other times the reminder comes from me consulting the Internet. Recently, I needed dimensional information on metric key splines for a reverse engineering project. Unfortunately the charts at my usual domestic tooling supplier stopped short of the size needed and the search continued deeper into the Google stack. A DIN standard was found but the price was more than I wanted to spend on an unfunded project. A little further into the stack a used textbook was shown with exactly the chart I was hoping for with a budget friendly price. I didn’t realize until it arrived that it was a standard machine design textbook from India. Packed to survive a rough journey, it was in better than advertised condition. Besides the needed metric key spline information, the textbook’s chapter on gears is much more sophisticated than any I have seen in an American undergrad textbook. It presents a detailed explanation of rack offset coefficient that would be worth a thorough reading by any gear designer. I have complained before in this space that American engineering schools do not allow enough classroom time to teach gear theory properly. The dean at one school blamed the required “core courses” needed for certification; many schools have few instructors with any practical gear experience anyway. Our domestic gear companies have long recognized the need to train their own designers. This has resulted in very localized understandings of “best design practices” that sometimes are at odds with the prevailing view at AGMA, ISO, or DIN. Gear Technology is dedicated to presenting the best technical articles available and by doing so we hope to broaden the consensus on what makes a good gear. Your content suggestions and submittals are always welcome. Articles need not have been previously presented at technical conferences to be considered.