Spindle brake for a mill-drill:

15" lever, rotates on stripper bolt... attach a 3-4" section of V-belt
to it with some button-heads. Make a block that can bolt down inside
the pulley housing. Thread the stripper bolt into there with the lever
attached. Lever rotates and engages the bottom pulley on the pulley
stack. Voila... spindle brake.

Worked awesome on my Jet... way easier to change tools... and now
there's a brake there to quell my urge to hit-the-brakes when I turn
off the spindle (automatic reaction from working on a Bridgeport most
of the time).

Good luck w/ the drawbar, tell us how it goes.