Over the weekend, due to a cold precluding much that was energetic I decided to deal with the sheared rack bolt on my tourer that has been awaiting attention since *cough*last August*cough*. Rack and mudguards have been using the same bolt ever since which offends my sense of neatness.
Proudly clutching my new #3 EZ-out (or nearest Screwfix El-Cheapo approximation) I drilled out the bolt, rechucked with the EZ-out, reversed the drill and had at it. EZ-out went in just fine. Bolt didn't come out though. Drill clutch makes that distressing rattling noise. "Ho-hum" thinks I. "Better remove the EZ-out and find out what's happened".
Accordingly switch drill to "forward". Same distressing rattling noise. EZ-out now very firmly stuck!
Cue much violation of Rule 2, faffing with visegrips etc. Eventually extracted the EZ-out by using the Reynolds chuck adapter for my SDS drill. That, being an old-skool keyed chuck (and nice and wide to boot) could grip the EZ-out firmly enough and allow me to turn it with enough force to unscrew the EZ-out.
After some consultation of the runes, I decided to drill the whole bolt remnants out and just put a new bolt through the whole, not bothering about tapping a new thread or inserting a helicoil. I then promptly utterly blunted my one 5mm drill bit requiring another trip to screwfix. With that out of the way, the repair seems to be holding up with only one Saturday morning lost, so far at least...