A customer in Tucson told me his shop used to fix lenses with a grinding stone and a prayer
I was cleaning a sticky aperture on an old 50mm last Tuesday when this older guy waiting at the counter started telling me how his dad ran a repair bench back in the 70s with nothing but a jeweler's file and a bottle of lighter fluid. He laughed and said most of what he learned came from just breaking stuff until it made sense, and honestly that hit me a little. Do any of you still teach the old trial and error way, or does everything start with a service manual now?
A buddy of mine runs a small repair shop out in the valley and he learned the same way. His old boss handed him a box of junk lenses and said fix these or toss them, no books, no videos, just figure it out. He told me he broke at least ten of them before he got the hang of cleaning out old grease without wrecking the threads. Now he can tear down a Helios blindfolded but he still keeps a service manual around for the weird stuff. Trial and error teaches you why something works, not just how. Books give you the steps but they never teach you the feel of it.