To sharpen electric hedge trimmers, place the blades in a bench vice and file each blade for about two minutes with a metal file tool. It is important to file away from the body to avoid injury.
It is best to sharpen an electric hedge trimmer on a flat surface, such as a table or work bench. Eye protection should be worn to ward off any small pieces of metal that might break loose during filing. It is also a good idea to wear thick gloves. Be sure to unplug the hedge trimmer to avoid any power surges during the project.
Using a pair of pliers, remove the bolt screw holding the blades in place on the trimmer. Once the blades have been filed, it is possible to test the sharpness of each blade using a sheet of printer paper. Move the paper along the blade and note whether or not it is easily sliced. If not, the blade needs to be filed more. Finish by applying a thin coat of linseed oil along the newly sharpened edges of each blade to prevent them from rusting. Be careful to sufficiently tighten the bolt screw holding the blades in place after sharpening is completed.