Bert Byfield wrote:
....
I had never before understood why some of the couplings had ridges and
some did not.

And now you do...

But also this pipe is only half an inch from the ceiling
so I can't get a regular pipe cutter to roll around it, ...

It should be possible to get a miniature tubing cutter around it if it's
1/2". If it's 3/4, they're pricey enough you may not want to spend the
money for a single use. But, generally there's enough flex in copper to
be able to make sufficient clearance unless there's a vertical also too
close.

But, if need to, the hacksaw will work. As you say, be sorta slow and
shouldn't have any problem.

And, of course, if it is just a pinhole, in all likelihood you could
simply clean and flux around it and fill the hole w/ solder and it'll
last indefinitely that way w/o the connector at all.

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