I've rebuilt a number of machines and machine tools from the ground up, here's a look at just one of them from abuot a dozen years ago.
Rescued from a garage in great mechanical shape, the five coats of paint were peeling off in sheets and there was muck everywhere. As with all things I rebuild, I took it down to every last bolt. (It's a sickness I have.) Removed nearly an inch deep layer of hardened oil additives and what not from the floor of the 10 gallon reservoir. I also changed the leadscrew of the head to a finer pitch. Going from 0.200/rev on a 11/2" dial to 0.100/rev on a 3 1/2" dial. In the picture on the previous page you can see the air operated tool lifter I designed and built for it. As I said, this is in storage now at a machine dealer. I had people wanting to buy it before it was even off the truck. If you've ever owned one of these they're hard to let go of, as they're a lot of fun to run, and awesome in their power and how they operate. It weighs around 8000 pounds. Sadly I eventually sold it because I lacked the room. If anyone is interested in it, it is for sale by the new owner.