It was a real treat to spend a day at a gear shop this week. After all these years, I still enjoy watching a round blank get transformed into a gear or pinion. Aside from the very enjoyable tour, I was there to teach about the process of making gears in all its wonderful complexity. Every shop has its problem parts, the jobs that demand special tooling, fixtures, procedures, and allowances if you expect to meet the drawing requirements. No two organizations have the same mix of people, tools, and machinery, so there is no “one size fits all” methodology available. Teaching a group of experienced machinists is different than presenting to newcomers. Each “student” has his or her own set of “horror stories” to share. Most have gaps in their knowledge that are best filled with a general presentation followed by lots of question time. I learn as much from these outings as the students due to the unique parts being made along with the “new” machines and processes on display. The latest iteration of gear grinders, for example, are able to meet the most demanding lead and profile modifications with ease. Seeing “old friends” amongst the machine tools is still fun, though. This particular shop has fully functional Illitron [ITW] inspection equipment in regular use. Respect, guys, as we struggled to keep those chart recorders working 45 years ago! Far from as easy to operate as a modern CMM inspection machine, the old veterans still make an accurate chart quickly once a specific job has been set-up properly. ITW’s Gear School was a right of passage within the industry for many years. I wonder just how many people Bob Moderow taught the basics of gear geometry, involutometry, and gear inspection. Thousands were trained to look at inspection charts and recognize the “problem” that needed correcting. Our technology has advanced on many fronts but the ability to diagnose the cause of a tolerance problem is a rare skill every gear guy or gear gal needs.