Quick and Dirty Hex Broach

I recently made a video on how to make your own quick and dirty hex broach from scraps or bar stock. This is a fun trick that we used to do at 5012 to clean up hex bores from 3d prints or machined plastic parts.

It’s far from a “good” hex broach but it’s nice to have in a pinch, especially if you have an arbor press that’s too small for a real broach.

Definitely a fun, useful part to make for lathe training as well!

Note: In the video, I use it to open up the hex bore on a colson wheel from vex. I do not recommend this for FRC drivetrain applications since they’re sized to minimize backlash.

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Do you have a video starting with a circular hole? You showed the example of colson wheel where you just opened up a hex, but can you actually make a hex with this broach?

Your’s looks great. I made one of these back in 2016 and we still use it a lot for broaching PVC end caps for quick roller prototypes.

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Here it is through 3/16" polycarb. Takes a couple of passes and you have to remember to clear the chips between passes. Perfectly serviceable for prototypes and low-load stuff.

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I’m cringing seeing your fingers near the business side of the broach.

Jeremy is a trained professional.

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The things we do for robotics.

#safetyFIRST

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Attach major mechanisms using 92965A583. It will save time because you’ll “handle” five of them simultaneously.

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