June 14, 2022
A critical step in designing a gearbox is refining the “study layout” and securing the necessary approvals so that detail design can begin. Although the advent of 3-D computer aided drafting [CAD] has changed the procedure greatly, the objective remains the same, i.e. — make sure all the decision makers are happy with the design before any effort is made to draw up the individual parts. Every design team has to suffer though a “false start” or two during the product development phase to truly appreciate the need for timely and fully informed approvals. Once detail drafting begins, the risk of drawing “errors” is too great and the effort needed to chase all the loose ends down too demanding for people to change their minds about things. In ancient times, say 1985, the lead designer controlled the only copy of the “study layout” and made sure that any “improvements” required by the customer, management, or manufacturing were properly executed on it before any copies were released for other purposes. You, as a junior minion, might be in the middle of preparing a preliminary bill of material for the cost estimators to use, only to have your copy of the layout abruptly yanked from your drafting board in favor of a newly updated version. But at least you got publicly notified. In today’s 24/7/365 collaborative design environment, someone half a world away could be changing the interface requirement without you even knowing it. Once the electronic file that serves as the modern “study layout” is distributed for comments, it is much more difficult to maintain revision discipline. Technology improvements speed up the design process. Collaboration makes more efficient use of resources. But people are still people and they need time to make good decisions. How much time depends upon the size of the project, the degree of technical difficulty, and the experience of those involved. The larger the team, the more opinions that have to be dealt with before agreement is reached. I once served as the “mall cop” on a multi-national project. It was my job to “observe and report” on the manufacture of the individual components. My opinion did not count, which was fine, as the seventeen other engineers [in four or five countries] had plenty of opinions already. It was very educational to listen in on those conference calls. On a professionally run project like that one, decisions took time but once they were made, they “stuck.” Team leaders are wise to ensure that everyone with a stake in the outcome makes a fully informed review of the design before declaring it ready for detailing.