Never be frustrated by a rusted nut and bolt again with this foolproof removal method. Loosen as much rust as possible off the nut with a wire brush. Tap the sides of the nut with a hammer to help the rust separate and fall off. Apply heat to the side of the nut for about a minute. When the bolt is cool enough to touch, spray WD-40 on and around the nut and bolt. Tap the end of the bolt with a hammer to loosen the threads and allow the oil to penetrate. Wait another minute or so for the oil to work, and then use your wrench to loosen. If all else fails, buy a nut splitter and crack that sucker in half. Always wear safety goggles when using a splitter. Painting an object prevents rust from forming by blocking water and air from reaching the iron or steel surface.