How Often Do I Sharpen Mower Blades?
- Sharpen the blade about every month under normal mowing conditions. This would be about every four times the lawn is mowed. Accelerate the sharpening schedule if the lawn is mowed more than once every week or if the lawn becomes particularly heavy between mowing.
Check the Blade
- Check the feel of the edge of the blade. If the blade feels rounded and dull it needs sharpening. Disconnect the spark plug cable from the spark plug to eliminate the potential of the engine starting inadvertently when the mower blade is turned.
- Blades may need extra attention if the mower has hit a rock or other hard object. These encounters can cause nicks or gouges to the blade which dulls it and in the worst case situation throws the blade out of balance -- with one side of the blade is heavier than the other -- which can cause engine damage. Follow the same safety precautions when checking a blade for damage as are used when doing routine inspections of the lawn mower blade.
- Disconnect the spark plug wire from the spark plug before removing the bolt that holds the mower blade to the shaft. Place the blade securely in a vise before using a file or a grinder to create a 45-degree angle edge on the leading edge of the blade. Insert a screwdriver through the hole and spin the blade to check for balance. If the one end of the blade spins lower than the other, the blade is out of balance. Return the blade to the vise and remove more of the heavy end of the mower blade before repeating the balance test.