Originally Posted by RickB
Can't seem to get the gasket to seat fully on bottom of sink where drain is. Can't tighten it any tighter else I'll break the plastic. I s there any kind of material or "goo" I can put in there to seal it?
Yes, plumber's putty is generally used despite whatever type of gasket that comes with the drain. Roll a thin bead like if you were making a breadstick, and then just wrap it around the drain before you tighten it. After you tighten it, the excess will just be squeezed out. Plumber's putty is easy to clean w/o chemicals.