On Jan 28, 2:49*pm, Oren wrote:
On Fri, 28 Jan 2011 15:28:58 -0500, wrote:
Make sure the point of the cone washer is entering the copper socket
and not catching on a flat surface. The cone nose must compress into
the copper fitting to clamp the tailpiece.

I had a cone washer leaking, so I grabbed one from my plumbing stash.
It leaked also. Apparently there are different sizes?

I would smear silicone rubber on evrything that could possibly be
involved in this and put it together, smear some more SR on the
outside of everything, let it sit overnight and see if that doesn't
work.