Knee mill draw bar failure

[woodchucker]

It probably stripped because it's been overtightened many times since it was new. I've seen guys tighten the drawbar as tight as they could get it with a 2' wrench. Bridgeport recommends tightening it to around 40 ft. lbs. The recommended torque for a 7/16-14 grade 5 or grade 8 bolt is 37 ft. lbs.

yep, it only has to hold it from coming out and moving about.
I avoid that on my mt2 quill... On it's own, it becomes tough to break free ... this morning was one of those ...

 

[Illinoyance]

Make the new drawbar an inch or so longer than the old one. Make the threads an inch or so longer. Make a spacer for the top of the drawbar an inch or so long. When the threads strip cut off an inch of drawbar and remove the spacer.