Allen screw removal from chuck jaw

[Random Orbital Bob]

Forgive the observation but using an impact driver for a fixing that requires a delicate torque setting is literally the worst possible tool you could use......it will continue to drive (while hammering) until all metal in front of it has vanished or the motor has burnt out!

 

[Phil Pascoe]

Our turning club uses one to fix faceplate rings and faceplates - then everyone wonders why they can never find screws that haven't been chewed up. :?

 

[Random Orbital Bob]

I didn't think you had electricity in Cornwall yet? :shock:

 

[Phil Pascoe]

Yes. And knives and forks.

 

[NickWelford]

Really? Wow!

 

[CHJ]

I use a torque limited drill/driver, I find it speeds things up no end especially when moving studs on Cole jaws.

Regarding the latter, to help avoid cross threading good quality screw cut stainless screws (as opposed to rolled thread) reduce this risk considerably.
This sort of thing

 

[deothedog]

This has happened to me and I use a centre punch put the point on the outside of the allen screw and tap the punch with a hammer in an anti clockwise direction it has worked every time so far

 

[SimonT]

This has happened to me and I use a centre punch put the point on the outside of the allen screw and tap the punch with a hammer in an anti clockwise direction it has worked every time so far

+1 not done this with chuck screws but plenty of others.

 

[Woodcrafts_UK]

Sorry to hear of the problem. I've not had it happen but may I offer some advice for the future. The sockets on these screws get filled with dust, so when you try to remove them, the allen key doesn't go fully home and is more likely to round out the socket. I always clean out the socket with a home made bradawl (sharpened masonry nail in turned wooden handle). And part of my chuck maintenance is to put some copper (anti-sieze) grease on the socket screw threads.
On the subject of replacement screws, you will be very lucky to find an exact replacement as the head diameter is smaller than a standard countersunk socket screw. That doesn't matter on some jaws, but any that have the socket screw 'down a hole' will need the right size head.
Good luck with getting the damaged one out.

 

[HappyPixie]

Thanks for all the suggestions. I ended up with a screw extractor which was surprisingly easy to use and less risky than my hamfisted self using a large drill on the small screw head. Risky!
As Woodcrafts_UK suggests, I do clean out the sockets before unscrewing. I use a pencil to clean out the socket with the assumption that a little graphite might be useful to ensure the allen key doesn't jam.
I also followed the link to the recommended stainless steel screws and was pleasantly surprised at how cheap they were. I picked up 50 for only a few quid and promise to retire the screws as soon as they show signs of wear!
Cheers y'all!