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How To Sharpen LawnMower Blade – Easy Steps

How To Sharpen Lawn Mower Blade

Your lawn mower will always clear up grass but how sharp the blade is will determine how fast, reliable and effective the mower will cut. A blunt blade will make the tip rough, wither easily and be open to pests and diseases. This is why you need to know how to sharpen lawn mower blade. The good thing is that you can do it by yourself and make your lawn look neatly trimmed, freshly cut, and very healthy without stress and in the shortest possible time.

 How To Sharpen Lawnmower Blade

The best way to sharpen a lawn mower blade is by using a sharpening stone and drill that’s designed specifically for the purpose of adding a cutting edge to the blade of the mower. Apart from using the drill and sharpening stone, other hand equipment like a rotary tool, bench grinder, angle grinder or even a hand file can be used to make the blade sharp enough to mow your lawn properly. Without further ado, let us consider the steps involved in making your lawnmower blade as sharp as possible.

 

STEPS REQUIRED TO SHARPEN LAWNMOWER BLADE

The following steps explain in detail how to sharpen the lawn mower blade in such a way that the cutting edge is easily accessible and you can actually see what you are doing and inspect any other damage that might have been done to the blade. The steps involved are as follows:

  • The first thing to do is to remove the ignition wire from the spark plug of the mower. This is to eliminate the risk of the engine accidentally starting when working on the mower. Remember it is the blade region you are working on so safety should be prioritized. It is also important to drain the gas tank so it does not spill while working. If the mower is cordless, then you will need to remove the battery pack.
  • Locate the bolt or screw that fastens the blade to the mower. You can locate it by tilting the mower to its side. Loosen the screw with the appropriate tool. If it is old and rusty, you can apply a lubricant or a grease, wait for like ten minutes and then unscrew it easily. You can use a wooden block as wedge to make sure that the blade does not turn.
  • When you have successfully removed the screw or bolt, take note of the side of the blade that faces upward and downward because when you finish working on the blade, the same has to be fixed in the same upward and downward position. No mistakes.
  • After removing the blade, there’s something else that must be done: use a knife to scrape off dirt from under the mowing deck. This area should be accessible to you because you tilted the mower. So scrape off dirt like mud, leaves, caked grass and other form of debris safely for about one minute from off the underside of the mower.
  • Before sharpening the blade, it is worthy of note to clean both sides of it by applying penetrating oil (penetrating oil, which is also known as penetrating fluid is used on rusted mechanical parts so they can come off easily. They are also used as cleaners and have low viscosity). After applying the fluid, scrub its surface with a brush that has stiff bristles.
  • We are getting a bit technical now. Fix the blade to a clamp or vice tool so that it is at an angle with one of the cutting edges facing upwards. The blades of the lawnmowers have cutting edges on both sides stationed on opposite ends. This cutting edges measure just about 3 to 4 inches long and does not include the length of the blade. Click here to learn how to repair your lawn mower.
  • Now the actual sharpening has to take place. After clamping the blade, you will need to use a blade sharpener that is drill-powered. This tool has an abrasive stone, round in shape, flat sharpening guide and 0.25-inch diameter steel shank. Full safety measures have to be observed at this juncture. Put the sharpening stone into a drill and then pull the trigger of the drill so it can rotate at top most speed. Place the spinning sharpener on the edge of the drill and then gently glide the stone up and down the cutting edge of the blade while applying even pressure.
  • Pause periodically between four to five back and forth movements to ascertain the sharpness of the cutting edge. Repeat this cycle until desired result is achieved and the blade is completely sharp. When you are done, remove the blade and then turn the opposite side so the other cutting edge can be sharpened too.
  • After the both sides of the blade have been sharpened, it is very important to balance the blade. Sharpening the blade has been found to remove some of its surface metal which could lead to an imbalance. This will cause wobbling and can damage the motor.
  • When you are through sharpening the blade and making sure it is balanced, return it back to its position on the mower. Use the screw or nut to fasten it. Replace the battery pack if it is cordless, fill up the gas tank and reattach the ignition wire as well. Your mower is as good as new and you can start trying out the new blade.

 How To Sharpen a Lawn Mower Blade

 

HOW TO SHARPEN LAWNMOWER BLADES WITHOUT REMOVING

By now you should have noticed that all the steps listed above will guide on how to sharpen the blade of the mower but you will have to remove the blade first.

But we won’t stop there because we know that you just might want to know how to sharpen lawnmower blades without removing it. It’s also easy so far as you follow our guide and apply all safety measures recommended.

You can sharpen the blade of your lawnmower without removing it by first tilting the mower so you can have full access to it, and then use an electric grinder, a metal file or a handheld grinder, all dependent on the tool you have at hand or the one you are comfortable with. Sounds too easy right? Well, there are some details we will have to consider.

STEPS ON HOW TO SHARPEN LAWNMOWER WITHOUT REMOVING THE BLADE

  • As always, start by removing the spark plug of the mower so the engine doesn’t start unaware while working.
  • Also remember to seal the cover of the gas tank so the gas does not sip out when you tilt the mower to the side. If the lawnmower is cordless, then you have to remove the battery pack.
  • As earlier mentioned, with the gas tank properly sealed, tilt the lawn mower sideways so you can have proper access to the blade. Use maybe a wooden block as wedge to make sure that the lawnmower is stable enough by placing it diagonally at the other side.
  • You will need another block of wood to place diagonally under the blades to stop it from moving while sharpening it as well. After placing the wedge, make sure that the blade doesn’t not move at all. Adjust the position of the wedge until this is achieved.
  • After this, clean the surface of the blade with a wire brush made from steel. As you know, you cannot sharpen a dirty blade. You can also use a penetrating oil for proper cleaning. If you notice dirt along the underside of the mower, it is advisable to scrape it off with a small knife.
  • All the things mentioned above are just preliminaries. The main work starts now. As earlier stated, you will need a metal file or a handheld/electric grinder to sharpen the blade while it is still attached to the lawnmower. Making sure to maintain the right cutting angle, place the sharpening tool on the cutting edge of the blade. After filing one part of the cutting edge thoroughly, repeat the same process for the other side of the blade. You have to be careful enough to observe that the cutting edge is evenly sharpened.
  • NOTE: unlike when you remove the blade, clamp it and make a back and forth movement on the blade, you only have to make one movement if the blade has to stay on the lawnmower when you are sharpening it. This means you will have to be lifting up the grinder or whatever tool at all times.
  • When you are through, replace the ignition wire, battery pack and unseal the fuel tank, all after you restore the lawnmower back to its original upright position. Now test run the lawn mower and make sure that the blades are as good as new.

Conclusion

Whether you choose to remove the blade of the lawnmower before sharpening it, or you simply just do not want the stress and you want to leave the blade on the mover while sharpening it, make sure you have all the required tool, follow closely the steps provided and most importantly, adhere to all safety precautions. Click here to learn how to maintain your lawn mower,