Many larger mower models utilize two or three blades running under the deck to cut grass in the lawn. These mowers cut grass more effectively and save valuable time as their double or triple blades are able to cut more grass in less amount of time. Double or triple blade mowers can cut thicker patches of grass to the desired height as multiple blades run through the grass and trim it.
Lawn mowers use various belt and pulley systems to time and position the blades in a manner that the blades do not hit each other or the deck during their rotation. It is vital to place the mower blades in the correct position so that the belt and pulley can time the blades properly and prevent accidentally causing the blades to hit each other or the deck.
Manufacturers set the blade positions to be parallel, offset, and staggered position depending on the belt and pulley system installed in their particular brand of mower. It is very important to set the blades in the correct position to avoid collision between the blades and between the blades and the deck of the mower to increase its longevity.
What Is the Correct Lawn Mower Blade Position?
There is no universal standard for the correct position of the blades in a mower. Different mower brands use different types of position depending on the exact mechanism that they have used to time the blades on their mowers.
What Is the Blade Position on a 2 Blade Mower?
Double blade mowers utilize stacked, parallel, and angled positioning in the mowers.
Stacked positioning is used in mowers that only have one blade mount but take multiple blades in the same blade mount. The blades are set on top of one another with nuts and bolts. These mower blades are set at an angle to each other and rotates at the same time. The correct position of the blades on this mower is specified by the manufacturer in the manual. The blades need to be installed keeping that exact angle that the manufacturer has specified. Make sure to install all the exact nuts and bolts in the correct holes.
Parallel positioning is used when there are two blade mounts on the mower and both blades are set at zero angle to each other. There are usually belt and pulley systems that move the blades during rotation in a manner that the blades do not hit each other and run underneath or top of one another.
Angled positioning is another method used by the manufacturer while setting up the blades on the mower. In this setting, the blades are set at an angle to each other while they are motionless. When they rotate, there are belts and pulleys that work to time the blades and prevent them from hitting each other. When you are setting the blades in this type of positioning, make sure to check that the belt and pulley system has proper traction and set correctly.
What Is the Blade Position on a 3 Blade Mower?
3 blade mowers use parallel, offset, and angled positioning while setting up the blades on the mowers.
In the parallel position, the blades are set at zero angle to each other. This method is only possible at larger deck mowers or mowers with internal belt and pulley systems to time the blades properly. While setting up the blades with this type of positioning system, make sure to set the blades with no angle between them.
Offset positioning is the most common positioning system in the triple blade mowers. In this setting, two blades usually have a parallel blade mount and the other blade mount is offset to these two. All of the three blades are connected with belt and pulley systems and these make sure that they rotate properly at the correct speed and time. Offset positioning system often automatically corrects the blade position to time them. Set the blades at the correct angle if that is not the case.
Angled positioning is used in 3 blade mower decks that have medium deck sizes. The blades are set at an angle to each other when they are stationary. During rotation, they avoid hitting each other because of the internal mechanisms of the mower.
What Is the Correct Angle for a Lawn Mower Blade?
There is no universal correct angle for setting the blades on a mower. It largely depends on two key factors, which are the intended position set by the manufacturer and the belt and pulley system that runs on top of the blades underneath the deck.
Manufacturers set the blades in their intended position while assembling the mower. This position is specified in the instruction manual and you can find this position in the images that they provide in the manual. Double blade mowers that utilize stacked positioning to install the blades specify the exact angle the blades should be set at for running properly. The blade mount has mounting holes and side holes that take nuts and bolts to be joined with the blade. The blades are stacked on top of each other and need to be installed in their correct position. Other dual blade and triple blade mowers that use parallel positioning or angled positioning will either specify the exact angle that needs to be maintained while setting up the blades or they have an automatic belt and pulley system to correct their position while rotating the blades. Set the blades at that exact angle if such angle is specified by the manufacturer.
The other factor to keep in mind is the belt and pulley system running on top of the mower blades to time the blades in the correct way. These belts and pulleys time the blades by moving them just a couple inches above or below to make sure that they avoid hitting each other while rotating. Setting the blades in the correct position might not be enough to ensure proper function of the blades and the belt and pulley systems must also be set in the right way. Make sure that all the pulleys are set correctly and none of them are wobbling or spinning incorrectly. Also, ensure that the belts have proper traction and are running the system properly.
What Are the Impact of the Lawn Mower Blade Position?
Lawn mower blade position ensures that the grass underneath the mower is getting hit with all of the blades at the correct angle and height. Correct blade positions make sure that no patches of grass are being left without trims. Multiple blades run on the same patch of grass to ensure that all grass is cut evenly at the desired height.
Lawn mower blade position also works to prevent the mower from hitting anything else other than the grass such as the deck, other blades, and the ground. If the blades are set at an incorrect position they will collide with these things instead of the grass and cause considerable damage to the deck, blades, and the ground. Blades will get bent and lose sharpness if they get hit with each other or the deck. This will not only decrease efficiency but can also cause serious damage to the overall structure of the machine. Incorrect blade position can also cause the blades to hit the ground while moving which can result in tilted soil on the lawn. Grass cut at the incorrect height and tilted soil can ruin the aesthetics of your lawn.
How to Determine the Correct Blade Position?
The correct blade position on a lawn mower can be determined by following the instruction manual provided with the mower by the manufacturer. Since there is no universal correct position or angle for installing lawn mower blades on the machine, each individual manufacturer installs their blades in different fashion. The manual will specify the angles that the blades should maintain during installation and operation.
The blades are supported by belt and pulley systems in the deck that control the blades and prevent them from unwanted collisions. While installing the blades on the mower, the user should also make sure that the belts and pulleys are functioning properly because their functionality directly affects the blades and their position in the mower.
There is no need to fix the position if the mower utilizes the automatic belt and pulley system and corrects the position by itself when the mower is operational.
How to Know if Your Blades Are Not in the Correct Position?
Blades are not in the correct position if
- Blades are hitting each other during operation.
- Blades are hitting the deck while rotating
- Blades are hitting the ground and scalping soil
- Blades are cutting the grass at the wrong height
- Blades are not leaving patches of grass uncut or unevenly cut
What Happens if You Put Lawn Mower Blades Upside Down?
Mower blades are angled in such a way that the grass clipping gets sucked in and disposed of through the chute. This pressure will be created in the opposite direction if the blades are set upside down which will hamper the discharging process. The blades can also end up hitting each other, the deck, and the soil if they are set upside down as the angles will be pointed in the wrong direction causing considerable damage to the blades, the deck, and the lawn.
What Happens if My Mower Blades Are Too Low?
Blades will hit the ground or cut the grass at the wrong height if the mower blade is set too low.
Can I Use the Same Blade Position Year-Round?
You can use the same blade position the whole year if the mower utilizes an automatic belt and pulley system to time the blades. Otherwise, the blades will require readjustment with regular usage. Follow the instructional manual to determine the correct blade position for your mower. Adjust the belt and pulley accordingly if they get loose or lose traction. Keep your blades sharp and balanced on all sides to ensure that the belt and pulley system functions properly.