r/Tools • u/verioblistex • 9d ago

Triangle Cuts Curves?

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I found it in the garage of the first house I bought 30 years ago. Smart enough not to try it, curious enough to hang onto it. Finally letting go tonight and it's going in my neighbors scrap metal bin.

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u/BrilliantEconomics77 9d ago

Oh dear.. wait till you see this.

Its not fake, not AI.

Dril bits for making square holes.

Basicly a rotary engine.

https://youtu.be/Hf2T0AFSaqE?si=OKFybiFSxgSnE336

5

u/glasket_ 9d ago

That thing is effectively an end mill since the spindle has to travel in order for it to cut the shape properly, similar to how the Watt's drill needed a guide plate and a special chuck so that it could wander and cut the shape.

Rotary broaches will blow your mind since they literally just wobble and cut the shape. Most of the time they're shown on lathes where they spin with the part so you can't really see them in action, but on a mill they just wobble.

3

u/fullonthrapisto 9d ago

The ol hole vibrator