I got a second large egg a couple of years ago and the daisy rocked on the neck of the dome. Hummmm, not a proper fit, I want (need) the daisy to sit all the way down to eliminate the gap between the ceramic vent and the cast iron for a good seal. This was when the "new" eggs were out with larger more pronounced dimples. New molds and a slightly different dimension as I compared my older egg to the new.
My fix, I shortened the side walls and I also ground out the lower insides of the daisy to accommodate the radius of the ceramic neck. (vent is shorter on new egg) A lot of work with wheel grinder and die grinder. I got the daisy to sit all the way down but it was then sloppy left to right. A patch of felt gasket inside the daisy fix that issue. Still, when all is said and done the egg should come out of manufacturing with good fitting parts. There are shrink rates calibrated for ceramics as well as cast iron and patterns for molds are created accordingly so that parts fit to specific tolerance. Along with a new egg there is a new daisy top so new molds all around for the large egg were created. I wonder why this issue of a rocking and tippy daisy was not addressed in design and manufacturing before management gave the "green" light to start production? :huh:
I'll get off my soap box now.
Good luck fixing the problem.