reply to PSWired
Re: Remove/repair broken drain valve (compressor) Tried an extractor that was tapered but the hole isn't deep enough to allow the extractor's wider part to contact.
For the hacksaw / notch option, the I.D. is really small and I'm not sure we'd be able to get enough depth or angle to cut notches.
What about driving a screwdriver in that's just wide enough to cut into the brass, but not too wide to damage the threads ?