Yeoman’s Lathe: Background and FAQ

Acquiring tools and the skills to use them is one of the biggest roadblocks to development in informal economies1. Those who do gain skills often are roadblocked from passing their skills on due to the lack of available tools.

Pat Delany, while at the Maker Fair in Ghana, met a young student of a carpentry trade school who spent 3 months saving to buy a Chinese-made wood plane. The obstacles to the resources individuals need to start economically viable enterprises are great, and competition is stiff. Tools are expensive and out of reach to all but a few.

As of 2011 07 28
[Yeoman’s Lathe concept. Image via author.]

What if the barrier to machine tools of acceptable quality were lowered?

What if you could build a metal lathe out of a few bags of concrete and scrap metal?

What if you could fill a machine shop with tools all made out of scrap and concrete? What if that machine shop made a business out of making more machines, populating other machine shops that made businesses out of fabricating parts for agricultural equipment, repairing auto parts, making lucrative sculpture art, or any of the myriad other niche markets filled by the informal economy?

What if communities with severely limited economic potential could bootstrap their fabrication and manufacturing ability to increase their industry and quality of life, without outside assistance or loans?

These are the sort of what if’s that motivate this project.

Pat Delany, inventor of the Multimachine, has been obsessed with machine tool design for developing communities for years. His pursuit of construction processes appropriate for non-industrialized regions is what led him to stumble across the designs of Lucien Yeoman from the beginning of the last century. Yeoman’s innovations for war materials manufacturing during World War I are being repurposed for the design of appropriate machine tools in the developing world.

Below is a FAQ for the project: please ask away so we can add to the list.

The 4-sentence breakdown.

“A lathe is a machine that spins metal, glass, plastic or wood to allow well planned and accurate shaping. Since the time of the Pharaohs lathes have been used to make things that would be otherwise impossible to form. [The Yeoman’s Lathe] project outlines a construction method first employed during WWI to rapidly build inexpensive lathes and other machine tools for the war effort. Using concrete, a lathe of any size required can be built by anyone who has basic tools, can buy or salvage wood for a form, some pipe, various metal bits and a few bags of cement.”

~Mr. Shannon DeWolfe

What is the goal or purpose of this project?

The purpose of this project is to create a design for a cheap, DIY lathe constructed out of concrete and scrap metal. The intent is to provide a means of production and fabrication capability for developing communities, education facilities, and hobbyists. Many attempts to provide technological solutions to problems in developing communities fail because those communities lack the infrastructure and capacity to repair or perform maintenance on systems. By creating a design for a machine tool that can be built out of locally available materials, we aim to increase the level of industry that informal economies in developing communities are capable of.

Who was Yeoman, and what does he have to do with lathes?

Lucien Ingraham Yeomans was an engineer and inventor born in the U.S. in 1878. He worked for a variety of manufacturing companies and held a number of patents for machine tools.

When the U.S. entered World War I, they suddenly needed to produce millions of artillery shells, guns, and other war materials. At that time the manufacturing sector didn’t have nearly enough tools to produce the materials required for the war effort.

“Conventional cast iron construction of machine tools is a slow and laborious process. The iron must be stress relieved and trued by skilled workers. Shell making lathes and gun planers and borers would take months just to get the machines built. The actual production of bombs, guns, and ammunition would be even longer into the future. The United States needed machine tools immediately.”

-Mr. Shannon DeWolfe

Here is a PDF article, authored and researched by Mr. DeWolfe, on Lucien Yeoman:

L. I. Yeoman’s Bio

Yeoman’s Innovation

Lucien Yeoman’s innovation was to reduce or eliminate the curing and machining time by using off the shelf manufactured components – bushings and the like – to provide the accurate machine surfaces required for a precision machine tool. The tool creation process looked like this:

  1. Cast the iron tool basic structure, leaving voids for bearings/bushings.
  2. Using a jig, place bushings, ways, spindles, and other components that require precise alignment.
  3. Pour type metal into the voids, casting the bushings and components in place.

This manufacturing method allowed precise machine tools to be built and ready for production in a fraction of the time required for traditional method.

Cast Lathe Bed[Lathe bed casting ready for bearings and ways to be assembled. Image from 1916 article.] 

[Bushings grouted into lathe bed to reduce construction time. Image from patent drawing.]

Here is a .pdf of Yeoman’s Patent for a shell-turning lathe using the process:

Yeoman’s Shell Turning Lathe Patent

And here is an article from 1916 that explains the construction process in greater depth:

Yeoman’s New Method for Building Lathes

Why Concrete?

Concrete is ubiquitous, cheap, and easy to work with. There is precedent for its use, both in Yeoman’s designs and others. See this 1987 patent for a process of forming concrete machine tools:

1987 Patent: Process for Forming Concrete Machine Tools

This article on building a 6-in turret lathe with a concrete bed is also related:

Building a Concrete 6-In Turret Lathe

Where can I find the latest design?



Also click through the different pages on the wiki to see more discussion of the different parts of the design.

Who is working on this project?

Pat Delany, inventor of the MultiMachine, has been researching and working on this project for 8 years.

I recently teamed up with Pat to help produce drawings, models, and to visually communicate the design.

The design process for this project is open and collaborative; many many people are involved and actively contributing to this project. Check out the Yahoo Groups sites below and subscribe to the email lists.

Why are you doing this?

Why not? Beats watching Family Guy reruns.

Background Resources

L. I. Yeoman’s Bio

Short Profile on Yeoman in American Machinist

Yeoman’s Shell Turning Lathe Patent

Yeoman’s New Method for Building Lathes

1987 Patent: Process for Forming Concrete Machine Tools

Building a Concrete 6-In Turret Lathe


1Making Do: Innovation in Kenya’s Informal Economy

3 Responses to Yeoman’s Lathe: Background and FAQ

  1. […] “releasing” our current design drawings, models, and notes for Pat Delany’s Concrete Lathe project and asking for comments, critiques, questions, etc. Engineers, machinists, appropriate […]

  2. The Wrencher says:

    Very commendable initiative for the developing communities. But will the concrete be able to take the shear stress as a cast iron tool do? Has there been any working model?

  3. Arti says:

    I have to give you very high commendation for turning pat Delaneys concept into what amounts,to me anyway, working sketches. I am well on the way to build quite a large machine based very much on the concepts detailed in your excellent drawings! Thanks! Arti

Leave a Reply

Your email address will not be published. Required fields are marked *