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In article , kens_at_sys_matrix_.net wrote:
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I would think, that since you can rotate the tap back and forth a bit,
that the tap extractors made with the little metal pins just may work
for you in this situation. You may even be able to slip a couple of
little pins down into the flutes of the tap yourself, and unscrew it
with a pair of needle nose pliers. HTH.

I've made a home brew tap extractor by using two sewing needles. The are
hardened & quite stiff, and just about the right size to drop into the
flutes of a tap. I've done a couple smaller taps this way, but it should
work on a 1/4-20 if you can find some large needles. A pair of pliers up
close can be used to twist them. Parallel jaw pliers would work best.

Doug White