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Three Gears are Possible

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If you’ve ever seen an image of three gears all interlocking or an odd number of interconnecting gears, like those gears on some British two pound (£2) coins, you’ve seen a gear configuration that does not work. However, three gears are possible. Mathematician and 3D printing enthusiast Henry Segerman shows us some creative examples in this video from Numberphile.

Segerman’s YouTube channel shares additional vids of these 3D printed gears, including a powered version of the triple gear:

the triple helix:

…and these Borromean hairpins:

All of the vids have links to his gears on Shapeways.

Next: More gear videos, including gears of all shapes and Turing Tumble. Plus: Building a House the Eco-Friendly Way with 3D Printing, 3D-printed Metamaterial Mechanisms, and Creating The Never-Ending Bloom: John Edmark’s spiral geometries.

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