In article ,
dpb wrote:

Joe wrote:
On Jul 11, 11:25 am, Red Green wrote:
Often when I take apart OLD plastic drain piping under sinks I find some
really sticky brown material on the threads. ...

Anyone know what it is or if it's still used?

Sounds like Permatex #3 Aviation Grade sealant. ...

Maybe, but doesn't seem at all likely for plumbing, particularly drain
lines that aren't pressurized.

I would strongly suspect it was a pipe dope but what specific one in
particular I don't know...

--

I was hoping someone would, as I ran into this stuff just a month ago,
too, in a house that had been recently remodeled. It was on the cleanout
threads. Very gooey, tenacious stuff.