1 earthquake: Rusty screws, do not use wrench a hard twist, in case of sliding screw unscrew six edges, twist off screw or screw wrench. In this case, hammer, lightly shaking handle of the wrench available, General vibrations loosen rusty screws.
2 knocks: with flat top hammer edge beats the corrosion of stainless steel nuts, it is easy to make nut loose. For example, bicycle handlebar ends bolt nut, according to the thickness of the pedal, made of metal, master force size striking the nut. Cast iron nut can be slightly larger, plastic tap. If it still doesn't work, then tapped the nut with hammer along the circle, you can easily remove the nut.
3 burned: some screws stainless corrosion is very serious, this method still does not work, you can "fight". Gas welding in oxidizing atmosphere with screws, nuts full Grill, and then to the Red screw on the drop a little oil. Heated screw is designed to make screws expands. Drops of oil to make screws cold shrinking rapidly, increasing gap between screw and stainless steel nuts and oil into the nut you can unscrew. But if a nearby plastic devices using this method.