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Sharpen your lawn mower blades!


Did you know, sharp lawn mower blades are necessary for a perfect-looking lawn? We are regularly asked by our customers why they have patches in their lawn, this is usually down to their mowing regime. 

Mowing with a dull blade will roughly rip through your grass, meaning it will begin to pull the grass up by the roots rather than trimming it – creating some ugly patches in your lawn. This will also leave your lawn more susceptible to disease and pests! 

Sharp mower blades promote good lawn care, keeping your grass green and healthy. 

How to tell if your mower blade needs sharpening 

You should regularly inspect the mower blades as over time they’ll eventually get blunted by usage. You can usually tell the blades need sharping by the lawn itself… 

  • Uneven grass height
  • The need to mow the same area multiple times 
  • Grass blades are torn instead of sliced
  • Discolored lawn – yellow or brown patches

Usually, how often do your blades need to be sharpened? 

It’s recommended your blades should be sharpened after 25 hours of use. However, this is dependent on how often and how long you mow for. As we’re creeping up to the last mow of the year, Winter is usually the best time to get your mower serviced and sharpen those blades, ready for Spring! 

How to sharpen the lawn mower blade
Safety tips: always disconnect the power source of the mower. You don’t want any surprises! Whether you’re sharpening by hand or machinery you should always wear gloves, eye and ear protection and long sleeves. 

  • Once power has been disconnected, turn the mower of its side. If necessary, ensure that the fuel filler and carburetor are facing up. 
  • If the blade is blunt or nicked, sharpen it. If your blade is damaged, it will need replacing.  
  • If sharpening by hand, you should aim to sharpen at a 45-degree angle and push the file in one direction along the blade. Your strokes should go from inside edge to the out. 
  • If sharpening with an angle or bench grinder, clamp the mower blade still and move the grinder slowly back and forth against the edge of the mower blade. 

The blade should be as sharp as a butter knife. Whereas a razor-sharp blade will dull more quickly. Once completed, grab a blade of grass, and pull it over the blade, if it cuts easily, it was a success! 

Checking the blade balance 

It’s important that when you replace the newly sharpened blade, that you check the balance of the blade. Any imbalance will cause vibration and affect the cut. Simply, hang the blade on a screwdriver or a pen etc. If it drops down either side, the side that dipped down is heavier and will need a few strokes taken off to make the balance even. 

Now you’re ready to reattach your blade and get mowing! Make sure it’s tight and the right way up! 

For further advice, please contact your local GreenThumb branch: www.greenthumb.co.uk/branch


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