Why do my baking sheets twist in the oven?

Better quality baking sheets would probably warp less. Your oven may have “hot spots” and “cool spots”, causing your baking sheet to expand/contract unevenly, which creates the “twisting” effect. This unevenness may also end up affecting your baked goods, so you may want to consider upgrading the oven, or at least rotating your baked goods half way through cooking.

Good luck!

@hannahsugs It even happens to the Calphalon pans.

Why was my post removed? I was serious.

This oven is probably projecting more radiant heat from the bottom than your previous oven.

Sheets with rims twist because the bottom of the sheet tries to expand, but the expansion is restricted by the upturned rim. The rim is slower to expand because it doesn’t catch as much radiant heat from the bottom of the oven (the rim is angled upward and so the radiant heat hits it at a glancing angle; the bottom catches it full on). The effect is exaggerated in steel pans because steel is a lousy heat conductor, so the difference between rim and bottom heat takes longer to even out.

In an oven that has less intense bottom heat, the rim will expand at a rate closer to that of the bottom, so there would be less twisting. One way to deal with this would be to either switch to aluminum sheets, or to put a sheet of aluminum foil on the shelf below the one your tray is on to deflect some of the radiant heat.