Screwed up drilling out a broken stud.

Good fix! I drilled, tapped and put a heli coil kit on the front axle control arm of my 7000 lb tractor.. All the bolts were stripped not just one.. They havent budged and have been in there for years, even takes moms abuse haha,.

 

When drilling out broken bolts or studs I use a left hand bit. The drilling will usually generate heat and the stud will come out on the drill bit. Maybe you were using a left hand bit and of course this will not work if you drill is slanted or off center.