4 Easy ways to Sharpen Lawn Mower Blades

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“The key to a quality cut is to use sharp, well-adjusted mowers. Dull, poorly adjusted equipment tears rather than cuts the grass, leaving a ready site for disease invasion and giving the lawn a frayed, brownish look.”

We know that it is crucially important to mow the lawn on time for the sake of the lawn’s good health and beauty. But it is also important to maintain your lawn mower. Otherwise, all of your efforts and hard work may go in vain.

Dealing with sharp-edged blades can be risky and may cause severe injuries, but if you are careful enough and you know how to do it correctly, you are safe.

The purpose of writing this article is to provide you with different methods to sharpen lawn mower blades. We will share step-by-step instructions to eliminate the chances of accident and to help you sharpen lawn mower blades like a pro.

All the shared methods will help you sharpen the lawn mower blades correctly so that your lawn may grow healthy and abundantly. So, read on.

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Method #1

Rub the file on the blade

It is a simple method that requires you to rub the file on the cutting edge of the blade, which is not a hard job at all.

Required Material:  

The following is the material needed for this method.

  • Hand File
  • Clamp or Vise
  • Ratchet set
  • Spark plug socket
  • Spray paint (Optional)
  • Work Gloves

Step #1:

Unplug the power cable of your lawnmower or remove the batteries if you have a cordless lawn mower. When you have ceased the power supply, the engine won’t start accidentally, which means you can handle your lawn mower safely.

Step #2:

Tip-over your lawn mower to a point where the blade is fully exposed, and you can easily reach it.

Step #3:

Have your work gloves on. Use the ratchet wrench and attach spark plug socket on it to loosen up the bolt that fastens the blade. Once the bolt is loose, remove the blade carefully.

Step #4:

Apply spray paint on the upside of the blade so that you won’t place the upside-down while putting it back. It is an optional measure, but if you are good at recalling the correct side, you may take the risk.

Step #5:

Use the vise to clamp the blade and keep it in place. If the blade is not clamped tightly, it may move while you are filing, which may cause an accident. So, double-check to ensure that the blade is held tightly.

Step #6:

Now, take the file and start filing the edge of the blade from a shallow angle. One thing you should keep in mind that the original cutting edge angle shouldn’t be changed. The manufacturers set the cutting edge angle of the blades to best suit the overall machine, and the lawn mower might not render the same performance with a different cutting edge angle of the blade.

So, file the edge to sharpen at the same angle rather than carving out a new one.

Step #7:

It is an essential step because, in this step, you will check the balance of the blade. If you have ground off one side of the blade more than the other, the blade will lose its balance that will not only deliver poor grass cuts but will also destroy your lawn mower.

When you are done sharpening the blade, glide in the center hole of the blade on a nail projecting from a wall. Keep the blade in a horizontal position and see if both sides are balanced. If one of the sides inclines downward, you will have to grind that side a bit more until both sides balanced.

Step #8:

Once the blade is sharpened, place it back and fasten it using your ratchet wrench.

Method #2

Our method number two reduces your efforts to almost none as you don’t have to use a file back and forth on the edge of a lawn mower blade. Moreover, it is the fastest method of sharpening blades.

Required Material:

You need the following material to apply this method correctly.

  • Bench Grinder
  • Vise (Only if you are going to use a handheld grinder)
  • Work Gloves
  • Glasses or any other eyewear
  • Ratchet set
  • Spark plug socket

Step #1:

Unplug the power cable of your lawn mower or remove the batteries.

Step #2:

You need to have your lawn mower tilted to a position where you can easily approach the bold holding the blade.

Step #3:

Put on your glasses and work gloves. Use ratchet wrench and spark plug socket to loosen the bolt so that you can easily detach the blade from the lawn mower.

Step #4:

Turn on the bench grinder and grind the cutting edge of the blade against the spinning wheel of the grinder. If you have a handheld drill powered grinder, then you need a Vise to hold the blade tightly.

Step #5:

In this step, you need to check the balance of the blade the way you did in step # 7 of method # 1. You will have to grind further a side that will incline downwards to balance up both sides.

Step #6:

When the blade is fully sharpened, attached the blade back, and the job is done.

Method #3

Sharpen the blade of lawn mower

This method employs a very traditional way of sharpening blades. It is common for sharpening scissors and knives. So, let’s check out how you will use this method.

Required Material:

Following is the list of materials you need to start with.

  • Gloves
  • Whetstone (Compatible with the drill machine)
  • Ratchet set
  • Spark plug socket
  • Drill Machine
  • Vise

Step #1:

Unplug the power cable of your lawn mower or remove the batteries.

Step #2:

Tip-over the lawn mower so that you can easily reach the blade.

Step #3:

Put on your gloves and use the ratchet wrench and spark plug socket to detach the blade.

Step #4:

Now, you want to stick the blade into the jaws of the vise and clamp it tightly. Hold the drilling machine and attach the whetstone on the front. Turn the machine ‘on’ and use the stone against the edge of the blade.

Step #5:

Slip in the center hole of the blade on a nail fixed on a wall to see if the blade is horizontally balanced. If not, hone on the side that out-weighs the other until both sides are equal.

Step #6:

After the blade is sharpened, use the wrench to fix the blade back under the deck of your lawn mower.

Method #4

It is the last method on our list and is for those who have push reel movers. The blades of reel mowers are spiral, and therefore, it can be a little challenging to use a machine to sharpen them if you are not that good at it. But this method works great even if you are a beginner.

Required Material:

  • Ratchet set
  • Work gloves
  • Grinding compound
  • Water

Step #1:

First of all, clean your push reel mower so that the grass clippings are out of the cylinder.

Step #2:

Apply grinding compound on the edges of the blades and leave it for few minutes.

Step #3:

In this step, you need to push the lawn mower backward and forward until the reel starts running smoothly.

Step #4:

Wash the compound with water, and your reel lawn mower is ready to mow your lawn.

Conclusion:

We want you to remember that sharpening the blades of lawn mower is not carving out new edges; instead, it means to refine the existing edges. Whether you are using a file, whetstone, or a grinder, you need to apply the correct technique.

If you are accustomed to using push reel mower and you are not an expert in sharpening blades, prefer using grinding compound because blades of reel mowers work like scissors. The reel blades and the bed knife has to be close enough to cut the grass blades, and if you don’t know how to do it correctly, you could damage any of the contact points between bed knife and reel blades.

How often should lawn mower blades be sharpened?

Blades of lawn mowers are usually made of reliable and durable materials. They last for years, but it is normal for them to get nicks and chips after some time. We recommend inspecting blades of your lawn mower after every half a year. If you have a small lawn and your mower doesn’t take much time to get the job done, it may go for a year without having blades sharpened. But if you have a comparatively bigger yard, you should sharpen the blades twice a year.

Do new mower blades come sharpened?

Yes! Most of them come sharpened. Whenever you are buying a new blade for your mower, you need to find the one that is compatible with your lawn mower.  We recommend purchasing the same blade your lawn mower came with. That will work better than any other blade.

Can a lawn mower blade be too sharp?

We recommend not making it too sharp. The too sharpened blade edge is prone to getting dull faster. The manufacturer doesn’t make it too sharp, and therefore, you have to follow the factory bevel for optimal cutting performance.

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