I just installed a new bathroom vanity countertop (St Paul by Home Depot) and installed a new Moen faucet. I used plumbers putty to install the drain and the drain leaked. I took it apart and used more putty than the first time and I still see a leak coming through between the nut and the threads. I didn't try silicone yet because I know it's a bear to clean up. Should I go the silicone route? If I do how long should i let it dry before testing everything? Should I apply silicone to parts other than around the underside of the waste seat? BTW the parts are all plastic and upon disassembly appear to be in good shape, I'm not sure what the sink is made of but I know it's some sort of man-made material. Any help would be greatly appreciated, thanks.