Internal keyway cutter - video

**Jon** · Oct 9, 2025, 10:36 PM

Internal keyway cutter. By Jay Fagan. 26:38 video:

**metric_taper** · Oct 10, 2025, 10:45 AM

It works, but I was thinking a drill does not have enough slow speed control, for a prime mover, and seeing the end, a better PWM controller may improve this, if it has feedback to provide the torque at low speed (controlled speed). I was hoping a repurposed gearbox with motor, vs the normal separate motor and gear box to drive the crank connecting rod, would make it a simpler build. Just need a bit more gear reduction.

Nice video of using a lathe for milling operations.

I could use my Milwaukee Hole Hawg, but I still use that (and it needs the spindle repair kit put in, as I twisted it off, drilling through thick steel and the bit grabbed).

**mansworld** · Oct 11, 2025, 04:22 AM

I saved myself the agony long time ago and purchased a HSS keyway broach set.

**metric_taper** · Oct 11, 2025, 07:38 AM

Same here, only time I would need one would be for a huge diameter bastard size internal keyway. And so far, I've not had that repair occur in my life's shop.

This guy spent huge amounts of time using his lathe's milling attachment (all undersized, but amazing machining work, with what he has).