In the 1980s, David Gingery published a series of books entitled Build Your Own Metalworking Shop From Scrap. The principle is reasonably straightforward: use common materials and scrap to bootstrap a set of progressively more complicated machines until you have a complete machine shop. Like many straightforward ideas, the execution turns out to be surprisingly complicated.
[Image credit to Arc Pacific]
The first step is to use a small number of commonly available parts to build a charcoal-fired foundry capable of melting aluminum and zinc alloys. Using that foundry and some hand tools (and elbow grease), a skilled hobbyist can cast and finish a small metal lathe. Using the items created already, one can make progressively more complex machine tools: a shaper (a machine for planing flat surfaces), a milling machine, a drill press, a sheet metal brake, and a set of indexing and change gears for thread and gear cutting.
I bought the complete series awhile back, and have read through it several times now. There are a few things that stand out from reading through:
First, Gingery wrote the original series over thirty years ago, there are some things in his “commonly available materials” that are no longer common (what the heck is hair dryer hose?). Anybody attempting to follow the Gingery build process today will need to make some substitutions.
Second, the shaper requires a lot of tedious work and is rendered almost entirely obsolete once the milling machine is built. Furthermore, the sheet metal brake is a welding project, and not at all related to the other machines; I see no reason for it to have been included in the original series rather than published as a stand alone Gingery book (of which there are several). With that in mind, I plan to exclude those two machines and design and build a bench grinder and metal cutting band saw instead, which I expect to see dramatically more use in my shop.
Third, the basic design for the milling machine is a rescaled and beefed-up version of the lathe, with the addition of a vertical feed (to allow movement in three axes). If I made the lathe sturdier to begin with, I could a) reduce chatter from heavy cuts, and b) make a temporary vertical feed and spindle to do light milling on the lathe (replacing the work done by the shaper in the original series). In fact, once I have the ability to move work in three axes relative to the tool, I could add a chuck to give it the ability to act as a drill press too. With a few minor alterations the lathe becomes a 3-in-1 multitasking machine, capable of turning, milling, and drilling (until I get those machines built).
For my own personal edification, I want to try to modify Gingery’s designs to run off a single line shaft. This means I don’t have to scavenge nearly so many motors to power my shop, and makes it dramatically easier for me to change the power source for the entire machine shop at a later date. What if I made a steam-powered machine shop? What if it was solar powered? Both sound pretty intriguing…
Regardless of how I alter Gingery’s designs, the first step is to make a charcoal foundry. I’ll list the posts I anticipate making as part of this project, and update them to be links as I actually write them. In this way, this first post will serve as a sort of living index to the others.