Continuing on our journey of re-imagining our go kart with 3D printed carbon fiber parts, I recently replaced the stock steering wheel with one designed from scratch to be lighter, more comfortable, and infinitely modifiable.

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The stock steering wheel from our Margay Go Kart

A go kart steering wheel needs to be three things: strong, stiff, and comfortable. The stock go kart steering wheel meets these requirements by being primarily constructed from stamped sheet steel for strength and stiffness and encased with a rubber overmold for comfort. This pound of steel should be undeniably able to withstand the bumps and jostles of the road, but it leaves much to be desired in the comfort department.

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An F1 steering wheel (source: Caterham/Lotus steering wheel)

By designing a steering wheel from scratch, I could model the geometry around the shape and size of my own hands and produce a steering wheel that would fit my personal grip. I decided to take inspiration from a number of Formula 1 steering wheels, dropping the circular shape of the original wheel for a more oblong profile.

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A first pass at designing a steering wheel for the go kart

With my first pass modeled in OnShape, it was off the Mark Two! A couple hours later, I learned that I had dramatically misjudged the shape of my own hands. With my new steering wheel in in front of me, I found it was cramped and awkward to hold. The flutes I had given the handles for my fingers to rest in did not line up with where my fingers naturally wanted to rest.

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The revised steering wheel design

Though my first print was not a great steering wheel, it was great tool for identifying where I needed to change my design. Among many small tweaks, I thickened the handles and removed protrusions that had cramped my fingers. And as with the go kart air restrictor, I took the opportunity to emboss the steering wheel with our new MarkForged logo.

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Using Eiger, the steering wheel can be selectively reinforced with carbon fiber

For strength, I selectively reinforced certain layers of the part with carbon fiber, particularly layers would experience the highest sheer loads from the steering shaft hub and mounting hardware. For stiffness, I used Eiger’s isotropic fiber fill to produce planes of fiber that specifically resist twisting loads. To learn more about our isotropic fill, read about how to best apply isotropic fill type to produce the strongest parts.

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Swapping out the old go kart steering wheel for the new 3D printed steering wheel

Out with the old and in with the new! With the steering wheel secured, it’s time to move onto another component of the go kart to replace with nylon and carbon fiber, and we hope you follow us as we do!

Want to see the Mark Two in action? Request a Demo today!