Guide To Electric Lawn Mower Blades
Keeping your electric lawn mower blade in great condition will help you mow faster and more efficiently. You will also have a better looking yard when using a sharp blade. In this guide we will cover how to take care of your mower blade, how to inspect it for problems, and how to change your lawn mower blade.
The first step in keeping your mower in great shape and your yard looking great is keeping the blade sharp. Sharpening your blade yourself will help you extend it’s life, as well as keep it cutting clean.
How To Sharpen Your Lawn Mower Blade at Home
To avoid the high costs of professional blade cleaning or buying a whole new blade, you can clean and sharpen your lawn mower blades yourself at home. This method can be time-consuming and otherwise not for everyone, but it is worth looking into anyway. Blades should be sharpened after 20 hours of use or every four months.
- Work gloves
- A scraper
- Safety goggles
- A power drill
- A blade balancer
- A socket wrench
- A vise
- A bastard cut mill file
- A sharpening stone
Once you have all your tools ready, it’s time to start the blade sharpening process. To sharpen your lawn mower blade to the best of your ability using these tools, proceed with the following steps:
How To Sharpen A Lawn Mower Blade
- Disconnect the wire that goes to the spark plug and put on work gloves to protect your hands.
- Flip over the mower with the spark plug side up while holding the blade with one hand to keep it from moving.
- Unscrew the blade’s mounting nut by rotating it counterclockwise using a socket wrench.
- Clean the blade using the scraper and check it. If the blade has deep, visible nicks from debris, it will be best to replace it. Otherwise, gather the tools to continue cleaning the blade.
- Choose one of three options you can use to clean your blade:
- The manual option– Clamp the blade using the vise and use the bastard cut mill file to sharpen the blade along the cutting edge using a one-way stroke. Follow the existing blade angle until the blade is as sharp as a butter knife, and do your best to cut the blade evenly on both sides. This is the slowest option of them all.
- The power drill option– The second-fastest method is cutting the blade using a power drill and sharpening stone. Fasten the blade in a vise and secure the sharpening stone in the power drill. The plastic guide on the sharpening stone should rest against the back of the blade to help you sharpen the blade at the right angle. Put on safety glasses, turn on the power drill, and move the sharpening stone from the center of the blade to the tip on both sides until the blade reaches butter knife softness.
- The bench grinder method– This is the fastest way to sharpen your lawn mower blade at home. To do this, hold the blade perpendicular to the rotating wheel of the bench grinder, and move it slowly along the cutting edge. Wear safety goggles to protect your eyes from sparks. Be careful not to oversharpen the blade; this creates a thin edge which makes it more prone to damage.
- Check the balance of the blade before remounting it on the lawn mower. If the blade is not balanced, it will be wobbly, not cut grass correctly, and strain the lawn mower engine. Set the blade balancer on a flat surface and put the blade up against it using the center hole. If the blade shifts to one side, remove more of the blade from that side until even.
- Reinstall the blade, reconnect the spark plug, and mow as usual.
Learning how to sharpen your blades is a valuable skill that can help you in a pinch when you do not want to wait several hours or even days to cut your lawn again. It can also help you save money, as professional blade sharpenings are not always affordable.
Why Sharpening Blades is a Good Idea
Keeping your lawn mower blade sharp gives it a longer life and allows you to get the best grass cut possible. If the blade or blades on the lawn mower are dull, it creates a safety hazard. Dull blades can also lead to poor health for the grass in your yard since grass grows back better after it is cut cleanly rather than in a choppy way.
Some of the downsides of using a less-than-sharp lawn mower blade on your grass are:
- Yellowing or browning of the grass because the damage to it prevents each blade from using photosynthesis to make food from sunlight
- Grass thinning as a result of less photosynthesis
- Fungal diseases start in tears in the grass blades and can spread to an entire field of grass if not treated.
- Weakened grass is more prone to heat damage or damage from pests and bugs.
When Should You Replace Your Electric Lawn Mower Blade
Now you know how to replace your electric lawn mower blade, but what are the signs you should look for that tell you it is time for a new blade? Fortunately, there are several, and they are as follows:
The Blade Has Become Bent or Twisted
If a lawn mower blade is bent, it will no longer cut grass effectively and needs to be replaced. This is true for any lawn mower. A lawn mower blade gets bent because you are hitting tree stumps, rocks, and other hard things while mowing. Using a lawn mower with a bent blade will eventually damage the motor.
You can avoid hitting these objects by surveying your lawn and moving them out of the way before starting your job. If you cannot move the problem objects, do your best to navigate around them. The most common sign that your lawn mower blade is bent is vibration because the blades have become off-balance from bending.
Lawn mower blades can also get twisted for the same reasons. Despite being made of steel, lawn mower blades are pretty sensitive and can be damaged easily. If you do not want to replace your blade entirely, you could also try straightening it with a hammer and anvil. However, this method is time-consuming and best suited for those that can use those tools well.
The Blades Do Not Have a Cutting Edge Anymore
Sometimes, blades will lose their ability to have a cutting edge. This can happen with any lawn mower and usually occurs when the manufacturer hardens only the blade’s original cutting edge. Over time, these blades will refuse to cut grass or even sharpen.
So, if you find that you are having to sharpen your blade more often, you should probably invest in a new one.
The Lawn Mower Blade is Not Performing Anywhere Near Its Usual Capacity
This is a very common reason why lawn mower blades need to be replaced. After a while, blades need to be removed and replaced because they just do not work the way they used to anymore. Sharpening could help, but this depends on the make of the blade and owner preferences.
Lawn mower blades are usually pretty affordable, so most people do not sharpen them. If you see uneven patches of grass after mowing, you will want to consider sharpening or replacing them.
The Nicks, Scrapes, and Scratches on the Blade Make It Hard to Sharpen
Many lawn mower owners sharpen their blades regularly to get the most use possible out of them. However, the blades will sustain so many nicks and scratches that they will be difficult to sharpen after a while. Whenever the scuffs are 2-3 mm deep, it is probably best if you replace the blade to have better cutting power.
Up until this point, you can either sharpen the blades yourself at home or take them into the shop to have the blades professionally sharpened.
Why Do Lawn Mower Blades Need to Be Replaced?
Much like a razor blade, lawn mower blades become dull, rust, and lose their cutting ability over time. These are all reasons why the blades on a lawn mower should be replaced regularly. If you do not replace them, you risk damaging the lawn mower, needing to work harder to finish a mowing job, and hurting yourself.
How Often Should You Replace Your Lawn Mower Blade?
For the regular homeowner, it is recommended that lawn mower blades be replaced every year. However, if you mow often, you will need to replace them more frequently because they will wear quicker.
Since annual replacement is just a recommendation, what factors can you use to assess when your lawn mower blade needs to be changed? These factors will be covered in the next section.
Do Electric Mower Blades Need Changed More Often Than Gas Powered Mowers?
If used on the same yard, an electric lawn mower blade will need changed about the same as a gas powered lawn mower blade.
The rule of thumb for lawn mower blade replacement is to get new ones annually so that you minimize the risk of damaging the mower. Blades wear down naturally as they come in contact with grass for all mower types.
Can I Use A Gas Mower Blade On My Electric Mower?
Lawn mower blades are usually specifically made for each type of mower. However, many brands make multiple blades that can fit one mower.
One brand’s blade can also be replaced with one from a different brand, as long as the length, thickness, width, hole numbers, hole sizes, and hole shapes match what your current mower needs. It is crucial to order the right blade for your particular mower.
How to Order the Right Lawn Mower Blade
Choosing the right lawn mower blade can be an overwhelming process. However, there are several criteria you can use when searching so that you can get the best fit possible. They are:
- Make and model– The badge or label on the blade is a great way to ensure you get the right one. You can search for the numbers online to find blades that would be a good fit.
- Blade part number– Each mower blade has a unique part number stamped onto it. Just searching with the number offers a list of websites selling the blade you need.
- Sizing a blade- This is the most commonly used method for finding the right blade because it is used when no other information about the blade is available. When sizing a blade, you need three measurements: how long the blade is in inches, the diameter of the middle bolt hole, and the blade boss shear pin to find the hole distance.
When ordering a blade, you will want to avoid fitting the wrong type of blade, fitting the blade with a bigger center bolt hole than needed, fitting the blade upside down, making the blade bolt too tight, or turning it the wrong way.
Types of Lawn Mower Blades
There are several styles of lawn mower blades available, each with a different look and advantage.
- Low lift– These blades are best used on sandy soil. They give a low drastic swoop over the blades and have low suction compared to other blades.
- High lift– The opposite of low lift with a high drastic swoop and high suction. The blade’s vertical swoop and minimal clogging make it best suited for bagging and mowing tall and compact grass. High lift blades only work well on a high horsepower motor.
- Standard/deck blades– The most common type of blade is slightly curved to increase airflow and improve suction to remove more grass.
- Gator (3 in 1) blades– These are also common blades and provide everything you need as a combination of high-lift, low lift, and mulching blades. They are typically more expensive than other blades due to their multifunctionality.
- Mulching blades– The best blades to switch to if your blades have a lot of wear and tear on them. They can be used for many different purposes and cut grass in several ways.
Choose your blade based on the wear on your current blades and the type of mowing work you want to do. Different blades exist to fulfill individual tasks.
Which Brands of Electric Lawn Mower Blades Are the Best?
A blade is an essential purchase to be able to use your electric lawn mower. However, not every blade is designed the same. Here are four of the best lawn mower blades available for purchase today.
EGO Power+ AB2101 21-inch High Lift Blade
- Specifically designed for use while bagging clippings with EGO Power+ 21" Lawnmowers
- Not recommended for use with the mulching plug
- Factory sharpened steel blade for excellent cutting performance
This high lift blade is made only for EGO Power+ mowers but maximizes the mower’s efficiency with its slightly curved blades. The blade is also factory sharpened and provides sufficient clearance through tall grass.
Greenworks 16-Inch Lawn Mower Blade
- 16-Inch mower blade compatible with GreenWorks 16-inch mowers
- Made with coated Steel
- Compatible with models 25142 and 25322
- Actual Blade length is approximately 1" shorter then mower deck size to allow clearance between blade tip and deck edge
This blade is pre-sharpened, coated, and made of steel, making cutting through thick grass an easy job. However, this blade is only made for model 25912 of the Greenworks mower.
Maxpower 561713XB 2 Mulching Blade Set
- Includes 2 commercial mulching blades for a 42" cut
- Each measures 21" long by 2-1/2" wide
- Replaces Poulan, Husqvarna, Craftsman 134149, 138971, 138498, 127843, PP24003, AYP7143A79, AYP7158A49, AYP9149A69, DPR20H42STA, TS14H42C, 2P4B9A, 9169A99 and 9178B99
This blade set is compatible with 42-inch Poulan, Husqvarna, and Craftsman mowers. They are made of steel, 21 inches long, and 2 ½ inches thick, making cutting through any kind of grass a breeze. The blade’s five-point star center hole makes it easy to install on your mower, whether you want to use them for cutting, mulching, or both.
Oregon 95-621 Gator Mulcher G3 Lawn Mower Blade
- 21" Length, 5/8" Center, 2.5" Width, 0.187" Thickness, 3/4" Lift
- The angle of the Gator teeth redirects the air flow to keep the clipping directly in front of the cutting edge. The longer the clippings remain in front of the cutting edge, the finer the size of the clipping
This gator blade fits 21-inch models of AYP, Sears, Husqvarna, Craftsman, or Poulan lawn mowers. It is 2 ½ inches wide and made from thick steel, ensuring the edge will stay sharp for a long time. Because it is a high-lift blade and has angled teeth, it allows better airflow and reduces the need for bagging while mowing.
The blade also cuts fast and does not leave grass behind, allowing for more efficient work.
Remember: It is important to find the correct mower blade for the lawn mower you own. Do not attach a blade that is not meant for your lawn mower.
How To Change An Electric Lawn Mower Blade
If you have an electric lawn mower, knowing how to replace your blade is an essential skill if you want to keep using it because you cannot cut grass well with a dull blade. If you try to do this, you may not be able to cut any grass at all after a while. To replace the blade on your electric lawn mower, adhere to the following steps:
How To Change A Lawn Mower Blade
- Unplug the lawn mower from its power source, whether that is a charger for a cordless one or an electrical outlet if it is corded.
- Wear safety gear such as rubber gloves and safety goggles to protect your hands from sharp pieces such as the blades and other sharp parts, as well as to keep your face from being scratched.
- Place both hands on the lawn mower deck and turn it over onto its side.
- Use a screwdriver or a block of wood to block the fan and keep it from turning as you work.
- Remove the old blade- unscrew the bolt that holds the blade in place by turning counterclockwise using a spanner, and take the blade off once it is loose.
- Look at the new blade and find the grass side or the side that makes contact with the grass. Align the hole in the middle of the blade onto the fan with the words “grass side” facing you. If the blade does not have writing on it, turn the blade’s sharp edge so that it points up onto the back-facing edge of the blade. The dull side of the back-facing end should be pointing towards the ground.
- Slide the blade onto the fan shoulder with the blade ends pointing at the front and back of the mower deck.
- Hold the new lawn mower blade with one hand and place the plastic blade insulator onto the blade, with one lip of the insulator over the blade’s top edge. The two lips are opposite each other on the insulator, one pointing up and the other going down.
- Place the blade spacer on top of the insulator so that it sits on the side of the insulator lip that faces you. Make any adjustments you need to align all the holes in the middle of the blade, insulator, and spacer pieces. If they are not aligned, they will not rotate properly and affect how the mower cuts grass.
- Wedge a 2 x 4 in between the back of the blade and the mower deck, and rotate the new blade clockwise until it makes contact with the wood 2 x 4 and does not move anymore.
- Insert the flange nut into the center-aligned holes of the blade, insulator, and spacer. Rotate the nut clockwise until it is tight and secure using a wrench.
- Remove the wood 2 x 4 and turn the lawn mower right side up.
Once these steps are complete, your electric lawn mower will have a fresh blade and be ready to use again. If, for any reason, these steps do not work for you, check to see if you used the right nut and bolt size for your lawn mower. Putting in the wrong size will cause parts to come loose and decrease the effectiveness of your lawn mower.
To help keep your lawn mower running well you should keep it clean. We recommend the product listed below to help extend the life of your blade.
- Designed with Cerflon, Ceramically-Reinforced PTFE
- Keeps grass & dirt from sticking
- Helps prevent rust & corrosion
The steps to replace your lawn mower blade are to unplug the mower, wear safety gear, remove the old blade, align the new blade, and secure the new one in place. Lawn mower blades should be replaced once a year, typically because they no longer work correctly, get bent or twisted, lose their cutting edge, and several other reasons.
If you are in need of a new lawn mower, be sure to read The Best Electric Lawn Mowers to learn what we recommend and how to shop for electric mowers.