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Lawnmower Blades: 10 things you should know

A lawnmower is a mechanical or electrical device whose main purpose is to trim and cut the grass using a rapidly rotating blade or blades. In ancient times before lawnmowers, the task of grass cutting and trimming was performed by workers who walked through the pastures and fields wielding small, sharp scythes. This process was extremely tiring and slow, but the manual cutting proved to be highly ineffective.

The first mechanical grass-cutting device came into existence in 1830. It was manufactured by Edwin Budding, an English textile worker, and was based on a textile machine that was meant to shear the nap of cloth. Budding created two versions of his device, the larger and the smaller one. The larger one was drawn by horses and was meant for large areas. The smaller one became popular among country gentlemen as it presented itself to be a fun, useful, and healthful exercise.

Over time, a lot of innovation was brought in this same machine, and now we can see numerous versions of a lawnmower with versatile features. Many companies like Honda, Briggs & Stratton, Lawn-Boy, Craftsman, etc., are considered market leaders when it comes to lawnmowers. These lawnmowers vary based on operation mode (electrical or gas-driven), engine capacity, Push or self-propelled, etc. Depending upon the yard a person owns, he could choose the best-fit lawnmower tailored to his needs.

Blades of the lawnmower serve to be an integral part of the machine as they are the ones who are directly involved in the cutting process. Thus, it is necessary to keep the blades sharpened and spick and span for the lawnmower’s optimum performance. In this article, we will answer some frequently asked questions when it comes to lawnmower blades.

1. Which side of the lawnmower blade is up?

When it comes to the maintenance of the yard and landscaping, the lawnmower is a very helpful tool. It is important for the optimum performance of these binding machines that the lawnmower’s blades are used correctly. This correct setting not only ensures accurate and optimum trimming but also provides the ultimate longevity of your lawnmower.

To know which side of the blade is up in a lawnmower, the first step to observe and identify which side of the lawnmower blade is dull and which side is sharpened. The sharpened edge could also be considered as the cutting edge. This cutting edge is honed to a point and must always face the ground while it would have a taper facing the sky. On the other hand, the dull edge is bent and must still meet the mower deck.

Thus while putting on the lawnmower’s blade, it is always necessary to keep in mind these steps as they would save you from the incorrect fitting of the blades on your lawnmower, which could not only lessen the life of the blade but also could result in the uneven cutting of the grass.

A few tips and tricks to identify the side of the lawnmower’s blades are as follows.

2. How to see if a lawnmower blade is correctly mounted

A few telltale signs indicate and ensure whether or not your lawnmower’s blade is up or placed on the right-hand side. These signs are relatively straightforward to identify on your lawnmower’s various models, making your job easy to set the blades correctly.

3. How to find the side of the lawnmower blade which should point down

Lawnmower blades could never be interchanged and should never be flipped. A sticker or stamp is always placed on the edges to identify the right-facing side. In addition to it, some blades also have works engraved or machine-printed onto the blades.

4. How to locate the cutting edge of a lawnmower blade

 The cutting edge is generally the sharper one as compared to the duller side. This is considered the most reliable and effective method to tell whether your lawnmower blade is up.

5. How to check if a lawnmower blade is wobbling: The wobble test

This step is performed as a final step to ensure whether the lawnmower blades are secure and stable. This is a very simple test. Following are its steps.

  • Step 1: Hold the mower blade with one hand and the deck with the other.
  • Step 2: Tug at the blade and then gently pull it downwards
  • Step 3: If the blade does not wobble, it is clear that it is on the right side and has its sharp edge facing the ground. In the case it is wobbling, ensure that it is on the shaft of the blade. Furthermore, tightening the securing bolt with a wrench may also help.

6. Which way does a lawnmower blade turn?

Knowing how direction the lawnmower rotates blades rotate is necessary to understand when removing or changing them.

Generally, the blades on many lawnmowers’ models rotate to the right, also called the clockwise direction.

If you plan to remove, sharpen or replace the blades, the retaining bolt should be rotated in the opposite direction. This is the left or the counterclockwise direction. Before removing the blades on your lawnmower, it is recommended to tip the mower on its side with the engine air cleaner facing up and then block the blade with a piece of wood to hamper its movement. Only be careful that the oil does not run to the wrong part of the engine when tilting the mower and that the gas does not spill from your tank.

7. Which way does a lawnmower blade bolt turn?

The cutting blade on various models of rotary lawnmowers is kept in place with the help of a threaded hex-headed bolt that screws into a blade adapter fitted onto the engine’s driveshaft. For replacement, sharpening or other reasons, blades need to be removed. As discussed in the previous question, the lawnmower blade bolt should be turned in a direction opposite to that of the blades.

Thus, as the blades turn in a clockwise or the right direction, the lawnmower’s blade bolt should be turned in the anticlockwise or the left path to remove the bolt, which would ultimately help remove and eventually replace or sharpen the blades.

If you remove the blade bolt, always pay attention to how the blades fit inside the adapter on the engine’s shaft. And on which side the blade faces towards the deck, and the exact order in which the tension washers were placed on the blade’s retaining bolt. When placing the replacement blade, be very attentive to the fact that the right side faces upward. Once the replacement has been made, one could tighten the bolt by turning it in the clockwise direction. If you plan to reattach the blade, you can mark it with a marker pen so you know what side should be up when you mount it back.

8. How much are lawn mower blades?

The blades of a lawnmower could be considered as one of the most essential parts of the machine, as it performs the most important and crucial task that is cutting the grass.

With time, the lawnmower’s blades should either be serviced (that is sharpened) or replaced. Buying new blades can be costly, yet if one takes good care of the blades, they could last many years. To get a feeling for the cost we have collected the price for a few blade types:

Blade TypeLawnmower TypePrice indication
Toro 22 in. High-LiftWalk-Behind Mowers$27
Craftsman 21 in. 3-in-1 BladeWalk-Behind Mowers$26
EGO 21 in. 3-in-1 BladeWalk-Behind Mowers$29
Craftsman 46 in. 2-in-1 Blade setRiding Lawnmowers$45
Max Power 46 in. Standard setRiding Lawnmowers$32
Max Power 42 in. Standard setRiding Lawnmowers$32
Ace 21 in. Mulching Mower BladeWalk-Behind Mowers$20

Ensure that you know what type of blade you need before purchase one. The blade should match your brand and mower type. This information can easily be found in the user manual.

9. How to lower a lawnmower blade

Depending upon the type of grass in your lawn, your grass should be cut to a specific height for an optimal result. The final cut of the season in the autumn also needs to be a different height. To change the cutting height following steps should be performed.

  • Step 1: Examine the type of grass that needed to be cut. This determines the height of the blades.
  • Step 2: Locate the lever to adjust the height of the lawnmower.
  • Step 3: Adjust the mower’s height by moving the lever to the latch to the proper notch for the exact size you are looking for. The general rule is that each crack is meant to signal 1/2-inch, and certain mowers will have labelings to show that. As mentioned in Step 2, if your mower has a latch for each wheel, each wheel needs to be adjusted while keeping in view the same notch placement.

These steps should be followed to lower or adjust the height of the lawnmower blades. For a riding lawnmower, almost similar measures could be followed except that a riding lawnmower has a knob or a lever that should be rotated either clockwise or counterclockwise or moved to adjust the blades’ height.

10. How tight should a lawnmower blade be?

Generally speaking, the blade’s bolt needs to be tight enough that you can easily remove it the next time you have to work on your blades. You should not be able to move with your hand by applying some pressure. The manufacturer should provide a proper tightening level expressed in foot-pounds, commonly found in the mower’s manual. Because the bolt rotates in a different direction than the blade, there is no danger that the rotation will loosen the screw.

Final Remarks:

This article has focused on lawnmower blades. We looked at various frequently asked questions and answered them briefly so that a lawnmower owner could have a clear and precise idea regarding the removal, height, prices, and types of lawnmower blades.