A cold breeze, uneven profiles, swirling your blade in the quench or boat oar pulling it thru the quench are all ways to warp a small thin blade. Now I always quench on a still non windy day and cut thru the oil with the blade. Moving it back and forth in a straight line. This advice was given to me by a FAR better knife maker than I. A bending fork ready to go could help you straighten a small bend if done right away. I sent mine in my anvil, turn on the toaster oven, tell the wife I'm heat treating and close the doors. Again advice from a better bladesmith than I am. I hope this helps.