I recently installed a new sink in my bathroom. I bought new waste pvc pipes and installed them from the sink to the wall. I thought it was all working fine but I noticed that at the top of where the pvc pipe connects to the metal sink pipe I have seepage. Basically the water is not pouring out, but it slowly collects and then drips down maybe 8 drops. So my question is; what do I do to eliminate that leak. I have a plastic washer on the metal pipe but nothing else.

Thank you,
Frustrated Seattle remodeler :)

Teflon tape on the threads sounds like it may solve your problem

This is a compression fitting and taping the threads on a compression nut won't stop anything. It's the pressure on the gasket that makes a water tight connection. One of three things might help. (1) Crank down a little harder on the nut to increase the pressure, (2) Coat the gasket with teflon joint compound or (3) change the plastic gasket for a neoprene one.
Good luck, Tom