Chuck Schultz is a licensed engineer, Gear Technology Technical Editor, and Chief Engineer for Beyta Gear Service. He has written the "Gear Talk with Chuck" blog for Gear Technology since 2014.
Today’s title does not refer to writer’s block. After 660 contributions to the magazine and blog, I still have a few things to cover ahead of my planned 2021 “retirement” from blogging. At the top of my list is providing some guidance on how you start a completely new gear or gearbox design.
Nothing is quite as challenging as figuring out where to start. What “old hands” do not tell you newbies is that we seldom begin with a completely blank page and you shouldn’t either. There is no crime in studying the work of others.
Actually, it is probably at least an “engineering misdemeanor” for anyone to think they are smarter than everyone else who came before them and do not need any help from prior art. We see this crime committed regularly with claims of “new” tooth forms that will “revolutionize” the gear trade.
Many incredible geniuses have worked in our field and left masterpieces for us to study and learn from. We truly stand on the shoulders of giants; be respectful and give credit where credit is due. I wrote a Fall Technical Meeting paper on Reverse Engineering [10FTM09] that upset some reviewers who felt differently but I stand by the position that most great inventions were inspired by prior art.
This is not to say that everything you see is worth “copying.” I learned more from fixing the flaws in old designs than from the things that “worked.” A good understanding of failures and their causes is necessary if you want your products to last. [My first FTM paper back in 1999 discussed the lessons learned in 15 years of rebuilding industrial gearboxes.]
I also encourage you to think about ways to use advances in gear making to build better products. Many “classic” gearboxes are limited by the technology available and used proportions that “worked” for the rating formulas in effect at the time. Standards are much more nuanced now and those designs no longer get favorable treatment. When you know better, it is incumbent upon you to “do better.”
Few things are ever truly “settled law” in engineering. What does not change is the imperative to “follow the science.” Here at Gear Technology, in both the magazine and the archive, we are dedicated to helping our readers built the best equipment possible.
Additional FTM references:
https://www.powertransmission.com/articles/0415/High_Contact_Ratio_Gearing:_A_Technology_Ready_for_Implementation/https://members.agma.org/ItemDetail?iProductCode=09FTM19&Category=TECH%20PAPER