Originally Posted by Michael in FtW
I agree with Andy. Lay a straightedge across the bottom of the pan and see if it bows out (convex - the center or some portion will be higher than the edge of the pan). Metal can stretch from heat. If so ... all you're going to do is invert the stretched area so that it will be concave on the bottom - and convex on the inside ... it would sit flat and not sit-and-spin but it still would not be in full direct contact with the cooking surface.
To really get it flat there are only two things that I know of that would work ... one would require you to know metal working (like in auto body repair where you use heat, hammers and dollies - I've never worked with stainless steel so I don't know if you can "shrink" it like you can other metals) or a machine shop that has a press and the correct size plates to reform it (the press will generate heat from the pressure and basically stretch the bottom back out flat). Maybe Goodweed will see this and can shed some more light on the methodology since he is a metallurgist.
Revereware is made by World Kitchen LLC. You might try contacting them and see if they can solve your problem? Here is the Workd Kitchen contact info
- and here is the Revere
website, and another way to email WKLLC.
Of course, Andy had a great suggestion ... "use this as an excuse to buy new pots and pans."
Though I'm not a metalurgist, I do know some things about metal. Steel is somewhat elastic. That is, if you bend it, but not too far, it will return to its original shape when the pressure bending it is released. Unfortunately, if you bend it past a certain "point of no return", it will remain in the new shape unless sufficient force is used to return it to its original shape.
Another property of steel is that it can and will stretch. But it is highly resistant to compression.
Let's see what this means. Take one steel bar, and let's use cold-rolled, mild steel as it is easier to work with. This bar has a one inch diameter and is fifteen feet long. If you exert pressure on the ends such that the bar bends in the middle, but only move it a few inches, when you release it, it will return to its original shape. When you bend it beyond that few inches, the inside surface of the bend remains unchanged while all layers of metal from the fulcrom point outward stretch, with the metal layer furthest from the fulcrom stretching the greatest. To bend the bar back, you apply pressure to both ends in the opposite direction. What happens then is that the metal at the inside of the bend stays the same, while the layers from that point to the outside skin on the outside of the curve have to stretch to allow the bar to straighten out. In the end, you have lengthened the bar just a little.
With your pan, as heat is applied, the cooking surface expanded relative to the sides. That is, the heat wasn't even and so the vertical sides did not expand at the same rate as did the bottom o fthe pan. Thermal expansion is nearly unstoppable and applied enormous force on the metal. If the expansion of the bottom surface exceeds the espansion of the sides, then something must give. The pan bottom bows toward the middle. causing the metal to stretch from its flat shape. if this bow is minimal, the pan cooking surface will return to its original shape. If the bow, or distortion, is large enough, then, the pan will remain in the ditorted shape. The only way I know of to get it back to its original shape involves heating the metal until it pliable enoough (soft enough) to be machine-pressed or hammerd into its original shape. But then the temper will be lost unless it is cooled properly by a true metalsmith. I would suspect that purchasing a new pan would be less costly and troublesome.
The pluss side of this is that you can usually give a pan that has bowed outward, a good whack with a mallet and it will bow inward, which makes it more stable on the stove. And the metal isn't so far away from the burner that it will suffer any great amount of heat loss. So unless you are cooking something that requires the food to stay centered in the pan, this shouldn't negatively affect your cooking.
How's that Michael?
Seeeeeeeya; Goodweed of the North