Tom Gardner wrote:

What size drill did you use for your tapped hole? Try a few thousanths
bigger, it won't affect thread strength and will make your job easier. I
have had luck making a forked tool to fit the flutes of the tap and back it
out but that's SMALL, you'll need a jewler's saw, some O-1 drill rod heat
treated just right, and a lot of luck. I think it helps if you burry some
chicken guts in the back yard during a full moon.
These are commercially available, go down to #4, and have worked pretty
well for me in the past.
http://www.waltontools.com/catpdfs/W...Extractors.pdf