Re: Plumbing: How to remove remaining piece of nipple from galv elbow

There are internal pipe wrenches that use a cam action to grip the
inside of a nipple but in a severeley rusted scenario I doubt they will
work well.

Use a hacksaw blade and a pair of vise grips to saw a slot through the
inside of the nipple and then collapse it in on itself.
You may damage a bit of the threads but nothing a good application of
pipe dope won't handle. If you are ballsy use a sawzall, I'd make the
cut on the upper side 12 o'clock position. worst case you make 2 cuts.

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