Woodworking | News & Updates

Woodworking | News & Updates

A pedal-powered lathe in SketchUp

David Heim is a veteran book and magazine editor specializing in woodworking. He has been writing about and teaching SketchUp for more than four years.

Last April, the editor of American Woodturner asked me to do a SketchUp drawing of a unique lathe. Designed by a young Canadian shop teacher named Scott Lewis, the lathe draws its power from a person pedaling bicycle cranks to drive a flywheel. This SketchUp project quickly drew me toward a program that introduces woodturning to less-developed areas worldwide.

pedal-powered latheScott Lewis’s lathe, a modern take on a centuries-old design.

It all began with baseball

In 2014, Lewis traveled to a school in the Dominican Republic town of Punta Cana to teach woodworking. “Baseball is religion there,” Lewis told me. He said he thought about bringing bats, but decided to bring a lathe so the kids could make their own. Transporting a full-size lathe—which can weigh more than 400 pounds—was obviously out of the question. So Lewis and two friends, Eric Foster and Chris Darnell, set to work designing a lathe that could be built on-site with a few basic tools and that wouldn’t need electricity.

They first tried a pole lathe and a treadle lathe, centuries-old designs that rely on taut ropes and foot-pumping to turn the wood. Neither worked. “I’m an experienced turner and in good physical shape,” Lewis said. “But running a treadle lathe was just too hard.” That’s when Lewis and friends turned to pedal power. Scott began by cannibalizing a colleague’s donated bike for parts. The rear wheel formed the basis of the flywheel; they cut off the part of the frame holding the pedals and cranks; and the front axle became a tensioning roller. Lewis and his father teamed up on the metalworking.

View of the repurposed bike parts used in the pedal-powered lathe design.

Scott packed the brackets, bike parts, and woodturning tools in boxes and suitcases for the flight to the Dominican Republic. Once in Punta Cana, they bought the wood they needed and enlisted the schoolkids to build the lathe.

The kids couldn’t wait to begin pedaling and turning. During Lewis’s three-week visit, the kids made spin tops, yo-yos, bowls, and—of course—baseball bats. Here are some highlights of the trip. (The video was done to coincide with Scott’s article in American Woodturner.)

SketchUp and Turners Without Borders

Turners Without Borders, a three-year-old program of the American Association of Woodturners, sponsored Lewis’s trip and wanted to make plans for his lathe available for free online. That’s where I came in.

Modeling the lathe in SketchUp became an exercise in reverse engineering. Scott didn’t create plans when he built the first lathe, but he sent me a simple SketchUp image of the lathe’s frame, with some dimensions. He also shared photos from his trip.

Working with that material and making some educated guesses based on my knowledge of lathes, I began to build the lathe and all its fittings in SketchUp. For some parts, such as the pedals and cranks and the bike wheel for the flywheel, I downloaded models from the 3D Warehouse.

Scott and I traded numerous emails to answer questions and have him approve changes as the plans developed. When I had the model complete, I began to break it down into scenes for the key sub-assemblies.

I used LayOut to arrange and dimension everything. A hidden-line image in the upper corner of each page shows the lathe progressing from basic frame to finished product. And I relied on the Cutlist extension to generate the materials list on the final page.

The finished plans—one version for customary measurements, one for metric—take up nine pages. Each page covers one major sub-assembly, such as the frame, the flywheel, the seat for the pedaler, the metal fittings and bearings, and so on. Take a look at this short video.

I finished the plans in early June. A few weeks later, I was in Pittsburgh for the AAW’s annual convention. Because of the work generating the plans, I wanted to know more about the Turners Without Borders program, so I sat in on one of their meetings.

Turners in less-developed areas may use Lewis’s lathe to set up a small business, becoming self-sufficient by selling the pieces they turn. In the future, TWB may also be involved in initiatives that could put this lathe to good use. It’s very gratifying to know that the SketchUp plans can help these ideas come to pass.

David Heim

David Heim is a veteran book and magazine editor specializing in woodworking. After a 28-year career at Consumer Reports, he moved to Fine Woodworking magazine. David has been writing about and teaching SketchUp for over four years, and never begins any project until he has previewed it in SketchUp first.

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