Having sharp lawn mower blades means you can achieve a better cutting effect in less time. Additionally, clean cuts protect the lawn. You know dull blades can create uneven cuts that make the lawn more likely to disease and pests. Sharpening lawn mower blades is essential for the health of your lawn and yard. This article is a guide on how to sharpen lawn mower blades, it’s easy to read and good for beginners.

mower blades

Must do before sharpening lawn mower blades

Before sharpening the lawn mower blades, there are a few things you need to do. You will primarily need two tools: a grinding wheel and a file. While the grinding wheel is a faster and more convenient sharpening tool, as a beginner, using a file can help you have better control over the sharpening depth.

Once you are ready to sharpen, make sure to unplug the power cord and remove the blades from the lawn mower. Inspect the blades for wear and cracks, and replace them if you find any issues. If everything looks good, clean the blades thoroughly before starting the sharpening process.

By the way, it is wise to have an extra lawn mower blade on hand for prompt replacement when needed.

Steps to sharpen lawn mower blades correctly

  1. Use a grinding wheel or file to sharpen the blades, ensuring even sharpening.
  2. Maintain the correct sharpening angle, typically between 30 degrees and 45 degrees.
  3. Follow the principle of alternating sharpening direction, meaning after sharpening one side, switch to the other side to maintain blade balance.
  4. Use a fine grinding wheel or file for further refinement to ensure the sharpness and flatness of the blades.
  5. After sharpening, clean the blades again and check for firmness and balance before reinstalling them onto the lawn mower.

(During the sharpening process, exercise caution by gently pressing the blades to prevent accidents or injuries.)

If you use a machine for sharpening, you can follow these steps:

First, adjust the gap between the bottom blade and the reel blade so that they make slight contact. The reel blade should produce a slight friction sound when rolled.

Second, apply specialized grinding paste to all cutting edges (blade cutting edges).

Third, connect the grinding machine to the reel blade and start rotating the blade (pay attention to the direction and make sure not to reverse it).

Fourth, continue grinding until a sand-flipping phenomenon occurs at the contact area between the grinding paste and the blade cutting edges.

Finally, slowly bring an A4 paper into contact with the rotating reel blade (in the cutting direction, sharpening is done in the opposite direction). Cutting the A4 paper cleanly ensures a good sharpening effect. If the paper is not cut neatly, it is necessary to readjust the gap and continue sharpening again.

How often to sharpen lawn mower blades?

Typically, it is recommended to sharpen lawn mower blades every 20 hours of use. The specific timing may vary depending on factors such as grass hardness, mowing frequency, and duration. If your mowing process frequently encounters debris like tree branches or pine cones, more frequent sharpening, such as every 10 hours, may be necessary. If you mow more frequently, it is important to pay attention to the health of the blades and perform regular maintenance and timely replacements.

How much to sharpen lawn mower blades?

Mower blades are not the most expensive among lawn mower parts. Generally, the cost of sharpening a lawn mower blade ranges from $10 to $20 per blade. Pricing may vary in different regions, and some providers may offer package deals or discounts for sharpening multiple blades at once. However, you can save a great amount by sharpening the blades yourself. It takes about 20 minutes when you sharpen the blades yourself though beginners may take a bit longer.