How to Sharpen Lawn Mower Blades?

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Lawn mower blades are meant to be Sharp but not as aggressively sharp as razor blades. As a user, you ought to be able to touch the blades and not get harmed, but they have to be sharp enough to get the job done in record time.

Don’t be deceived, a razor sharp blade does not necessarily translate to cutting grass well,  an edge that is too Sharp has the possibility of rolling over grass than cutting it smoothly.

The best way to have your blades sharpened is by using a dedicated blade grinder as opposed to using your hand or any other bench grinder technique. Bench grinder technique or hand grinding/sharpening consumes too much time and often leads to inconsistent results.  

Most bench sharpened blades results in blades that are sharp at some edges and very blunt at other edges. This is not what we want for a proper cut

Read on to find out how to sharpen lawn mower blades.

When is the right time to Sharpen Lawn Mower Blades?

How to Sharpen Lawn Mower Blades

The more you use your mower the more frequently you should sharpen the blades. If you use your mower for residential apartment to cut around the yard and garden, sharpening it once a year is appropriate.

However, if you are into professional landscaping business or you have large acres of land to maintain on a regular basis you should look into sharpening the blades frequently.

Read more:How to Change a Lawn Mower Blade?

Sharpening By Hand (Inconsistent results)

To sharpen the mower blade by hand, securely clamp the mower blades to your workstation. Do it in a way that makes it convenient for you to work on it.

Most people prefer the blade sticking out from the workstation and roughly at their waist region so that they can work on the mower blade while sitting down.

Place pieces of paper or newspaper just below the workstation to catch the tiny metal filings that dropout for easy cleanup.

Sharpening with a file

Follow these procedures to sharpen your blade with a metal file

  1. Place a metal file along the Cutting Edge of the mower blade
  2. Now stroke the metal file inside and outside of the shiny surface of the mower blade
  3. Repeat the process until a clean shining surface emerges just at the edges
  4. Repeat steps 1 through to 3 for the other side

Sharpening with a Machine

The best way to get your blade sharpened is by using a dedicated machine grinder. Grinding by machine is the best way to get consistent results from every sharpening activity, but before you use a machine observe some common safety practices and precautions before, after and during working.

Things you need to sharpen your Mower blade by Machine

  • A dedicated blade grinder
  • Hearing protectors
  • Gloves
  • Protective eyewear
  • Lawn mower blades

Precautionary Steps to take before machine sharpening begins

  • Check the work area to make sure the grinder is properly supported on a level plain surface.
  • Properly clean the work area to ensure there are no inflammable materials around. Sharpening the mower blade often results in Sparks that can ignite anything that is flammable around. Therefore ensure nothing stays around the area that can ignite fire.
  • Inspect the dedicated grinder inside out. Lookout for cord breaks or terminal damage to a wall socket or anything that could hamper the smooth sharpening of the mower blade. Fix any of these errors as soon as possible.

Using a dedicated mower blade grinder

  • First and foremost determine the orientation of the dedicated grinder. Is it meant for left-handed individuals or right-handed individuals? Be on the lookout for the straight cutting end of the grinder. If it’s facing right, then it’s for right-handed individuals if it’s facing left then it’s for left-handed individuals.  Ideally you should check the blade grinder manual four proper directions.
  • Next, adjust the grinding angle of the blade. The kind of Blade to be sharpened will determine the angle at which the grinding machine will be adjusted. Some blades are set at an angle of between 25 to 30 degrees. For example, all Oregon blades according to the manual are sharpened at an angle of 30°.
  • After you have determined the angle, set the blade on the bench and match the angle of the stone face in such a way that the stone is almost directly touching the face of the blade. Adjust the angle accordingly if the stone is not directly touching the face.
  • Next, Plug in the machine grinder and power up the device.
  • Consult your manual for sharpening details. Most will require that you set the motor to switch forward or reverse, effectively rotating the stone counterclockwise.  Onceit’sin emotion all you need to do is draw the blade closer to the stone till the sparks of the sharpening are thrown to the opposite side of the mower blade.
  • Continue steps 5 until you’re satisfied with the sharpening result.

Additional precautions while operating a dedicated grinder

  • While sharpening your blade with a dedicated grinder, stand facing front of the grinder and never at the sides to prevent spark damage.
  • When you power up the dedicated grinder make sure the stone comes to full speed before you start working.
  • Hold the blade with both hands why the sharpening.
  • In the direction of the cutting, allow the wheel pass the cutting edge blade back and forth.

Reinstalling the Blade after sharpening it

After sharpening your blade in whatever means you choose, place it in water to cool it down. After that, lubricate the main bolts so that they do not rust before placing it back in the lawn mower.

Tighten the bolts making sure you get the orientation of the blades right.

Lastly, avoid using a hammer to make the boat tighter this might cause a little disruption.

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