All in all (4 pages worth) a fascinating read. To put things somewhat in perspective, I do some metal working. But I also do framing carpentry on an old house (1887), some "stick it together" welding, building small models(trains), and am was professionally a mill and marine electrician, from age 18. The end result is I have trouble maneuvering around tools and stock now with a walker. In most cases, if I had a specialty job, I would outright purchase the special tooling needed. Or like the pilot shaft for a Ford 300-6, make it. And never throw anything out, no matter how trivial. What it comes down to is "I would much rather to have something and not need it, than to need something and not have it." Almost everything I have piled up in corners and on shelves has been used at least once and I may need it again some day.
There are a few exceptions; a set of guage blocks, a sine bar and vise, a set of "precision angle" standards, things of that nature. I may never need any of them but they take up so little space relative to stuff I do use, I just let them get covered up. And should the need arise (unlikely), they are here, just covered up. There are a few archaic tools that I don't normally use, hand drills and saws and the like. But on those rare occasions where I need to make a small hole in a wooden stick, I can do it at my desk without having my "shop" in the house.
I will concede that I don't do precision machine work. I do try to make parts as precision as possible, but it's mostly repair work where tolerances are sort of loose anyway. The most precision work I do is to make model locomotive frames, cutting axle slots and the like. But like my trains, much of my precision tooling was bought off eBay and other "discount" sites for used pre-owned hardware. Salvage houses for esoteric devices in debatable condition. . . The angle blocks were corroded, I cleaned them up except a few that are badly corroded. But if they measure a 30 degree angle plus or minus 30 seconds, they are usable.
The bottom line is they didn't cost very much and work for what I do. Space I have, money I don't. My work space is sort of "cobbled" together, an old house next door to the residence and a homade storage shed that I built to resemble a barn. (24X32) If I don't need it this year, I might next year. And likely have it around somewhere.
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