I thought this was a common problem, but couldn't find anything when I did a search.

We installed a smooth top cooktop in our kitchen in the fall. This is when I realized that several of my pans that I thought were flat on the bottom were not! This includes Calphalon that I paid a great deal for! Anyway, I went out and purchased a new set of hard andonized cookware. I even took a ruler to the store and verified that each pot was indeed perfectly flat on the bottom. Now the largest skillet is warped on the bottom and my newly purchased wok did the same thing last night!

I understand the basic principals of heating metal but that doesn't help my dilema! Am I doing something wrong?? Can someone please advise me on what to do? This is making cooking quite difficult!

Thanks! Kay