From the Founder, Pat Delany:
My role: to revive the original concrete lathe concept, to update the technology by 100 years and to shrink it from a ten-ton machine to one that will fit on an artisan’s workbench.
For instance, Yeomans used a still-secret (and highly toxic) metal alloy in his original construction, which we’ve replaced with non-shrinking cement grout — common worldwide. Our version also dispenses with Yeomans’ massive, industrial-scale alignment frames (jigs), replacing them with a method that can be used in a home workshop or by artisans in the developing world.
Replacing these two elements was not a simple task: it required four years of hard work to come up with solutions that are applicable NOW and around the world. Though our plans start small, they can expand: using our designs, someone could build a version as large as a railroad locomotive. This is a scalable solution to the problem of local manufacturing for local needs, since our version of the concrete lathe can work for a single artisan all the way up to a full-scale factory.
The following documents are absolutely key to understanding how to build the Concrete Lathe, the core piece of the Open Source Machine Tools project.
- Lucien Yeoman’s original 1915 patent application for the concrete lathe, providing an overview of how the machine works [PDF].
- “A New Method of Building Lathes” (June, 1916), a Machinery magazine article that lays out the basic concepts behind the concrete lathe [PDF].
- American Machinist magazine article about the Yeomans concrete lathe. A later article with larger photos of the lathe-manufacturing process (link opens in a new page and goes to a Google page that contains a scan of the article).
- “A Small Bench Miller,” a Popular Mechanics article by Joseph V. Romig from the 1920s that inspired the search for/revival of the concrete lathe [PDF]. This article is one of the first practical descriptions of how someone in a home shop could build the key working parts of a lathe using steel shapes available to anyone. Despite its humble origins, this basic idea is still widely used in industrial-scale CNC (automated) milling machines today.