....
How is the CNC drawbar engaged? (curious) I thought drawbars were
just glorified, dual-threaded long bolts which engaged the bit from
the top, drawing it into the tapered spindle hole.

power drawbars have splined ends with points on the end of the
splines. There's a female mating spline on an electric impact wrench
and an air cylinder to drop it in place.



Deep 7/8" impact socket and pneumatic impact wrench, Karl. Use a
large diameter hose and high pressure air for maximum torque. Try it
both ways to rule out left-hand threads. Maybe wedge an old bit in
the collet to slow down the turning if it slips on you.

Wish I'd ask you BEFORE I broke it

Karl