The strata were what I was thinking of. Great idea to make them (the wedges) with plastic....must have been having a blonde moment since I was thinking of the wedges, not the fact that they make a circle! Thank you for all the tips. The strata units help with the cupcake problem somehow. I have made a few circles with the strata and they always come out flat. (amazing for a free-wheeling quilter like me)
RQ