After dissembling my sink drain and putting it back together with a new gasket, I had hoped to have stopped the leaks, but now I'm finding I still have a little leak -- in the location shown in the attached picture, right where the red circle is.
I didn't put anything there because I don't know what to do. (Plumber's putty? Silicone?) I just hand-tightened it -- though this was difficult because I couldn't figure out exactly how it screwed together, and there was a very sharp lip that almost cut me.
It doesn't appear I'm getting any leaks from the top of the assembly (where you can see a black rubber gasket). Only at the juncture circled in red. How do I seal this little juncture?
The gasket at the connection from the drain to the P-trap (elbow) may be worn out or missing.
I suggest getting a new P-trap system with all new gaskets.
Thanks for the photo!
Plumber's Putty has traditionally been used in joints like this to fill and seal.
You might also have seen a rubber or plastic compression gasket like the one shown by the red arrow.
It actually installs where the green arrow is pointing and helps seal the joint in question.
You'll find replacements in Plumbing.
Be careful when handling any sharp objects!
If cut during a repair, stop immediately to clean, disinfect, and bandage the cut.
If all else fails, consider Stretch and Seal tape.
This plumber's tape looks like electrical tape, but stretches and seals leaks.
On passive, no-pressure fittings this tape is easy to apply and stops leaks quickly.
Thanks so much for the incredible help here.
I did end up replacing the whole p-trap. It was a little hard to figure out being that I needed one special connector, so I had to disassemble my old one, bring it into the store, and have an associate help me figure out exactly what I needed to hook it up.
I ended up going with a plastic (not metal, as the original) one, since the cost savings were significant and this is under a counter so I'm not concerned about looks.
The leak appears to be totally fixed and I could not be happier. Plus of course that feeling of accomplishment for not having to resort to calling a plumber in, and fixing it with my own hands.
Thank you everybody!
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