The lid on my 22.5" Platinum had developed an almost sandpaper like finish on the outside of it. I have tried various cleaners in the past with no success. Yesterday while I was detailing my roadster it dawned on me to use a clay bar on the Weber lid. A clay bar is used in automotive detailing to suck contaminants out of the paint before your apply your favorite wax/sealant (Zaino in my case). I kept the surface of the lid wet with soapy water and went to work. In 10 minutes the surface of the lid was smooth and like new again.

yea, the heat seems to cook stuff on the lid. i use fine steel wool and a cleaner.

use a white (color) scotch brite pad. they will not scatch the finish like. works great