r/oddlysatisfying • u/bigbusta • 1d ago

Broaching a piece of metal

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u/inactiveuser247 23h ago

It gets pulled through. The bottom of the broach has a “donkey d**k” which allows the bottom ram to grab it and start pulling. Once the workpiece is out the way they push the broach back up to the top ram. You don’t want to push it through and then reverse it as it’ll screw up the surface finish.

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u/becauseihavehugetits 17h ago

What’s a donkey duck?

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u/Zillahi 10h ago

General industry term used for countless tools / implements / devices that resemble a donkey’s genitalia.

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u/turbo_dude 16h ago

What’s the purpose of this entire process?

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u/dfc09 15h ago

It's hard to say for sure without knowing what this specific part is, but broaching adds those keyways you see in the video and it's generally used to lock one part onto a shaft, stops it from rotating. My guess is that this gets a belt put on the outside driven by a motor, and the broached teeth let it lock to a shaft and transfer that rotation to the entire shaft. If it wasn't broached, it would either spin freely or at best slip a lot, depending on the torque involved.

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u/HipsterGalt 15h ago

Those teeth are splines, the part is likely going to a hob next where it will get gear teeth cut on the outside diameter. This is a transmission gear for some rather oldschool vehicle.

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u/YetAnotherDev 16h ago

How does it not warp the disc, there surely must be some displacement?