Why do certain cookie sheets warp and buckle in the oven?!
Answers: I have some inexpensive (chefmate brand) cookie sheets that as soon as they come in contact with a hot oven, the opposite corners warp up. Once cooled they return to normal, but it is really bothersome when you have a pie pan on it to catch spills, then the sheet warps and the pie pan tilts and all the juice runs out the side!!! How can I prevent this??
Voila; you know what a junk sheet is . Buy em at William Sonoma they have non stick also (not Teflon) No warp no Bull----You can also get good sheets at a restaurant supply store
They usually warp when one of two things (or both) happen:
1. They are cheap-o pans from like WalMart
OR
2. They are made from aluminum.
All cookie sheets expand and contract with temperature changes. Cheaper, thinner metals will distort more violently producing a warping of the surface such as you are experiencing. Try filling the cookie sheet with water. This will stop the warping as well as keeping your pies moist!
The buckling and warping is caused by thermal expansion.
Thermal expansion is an unavoidable physical phenomenon in which all materials expand when they are heated. However, the amount of expansion is dependent on the exact material. The buckling and warping with your chefmates is caused by the cookie sheet being too thin and flimsy, and is probably made out of an inferior cooking material. Better cookie sheets (and pots and pans) are made out of materials that don't expand too much as to be noticeable when they are heated.
Maybe you could use a disposable roasting tin to catch the oil spills instead?
Buy new commercial sheet pans for baking, etc: The pans you have by chef mate are probably to thin and that's why it warps. Go to any restaurant supply outlet to find them
i used to use the cheapos but got tired of the warped pies and funky looking cookies. so i invested in some good ones.