Sharpening a dull lawn mower blade will save you the trouble and money of buying a new one and cut your grass more effectively.
Step 6: Prepare the bench grinder. Set the rest on the bench grinder to the angle taken from the blade. This will help you to guide the blade so that the angle remains the same across the length of the cutting area. Wear safety glasses during the grinding process, and make sure the shield of the bench grinder is set in place.
Set the rest and the shield of the bench grinder.
Be sure to disconnect the spark plug wire from the mower spark plug before attempting to remove the mower blade. Wear safety glasses and gloves when sharpening the mower blade. After sharpening your blade and putting the mower back into use, regularly check that the nut securing the blade is tight.