Lawn Mower Question Series (2 of 6): What’s The Best Type of Blades To Give My Lawn The Cleanest Cut?
15th Aug 2012
This is the second post of this series of the most common lawn mower questions that we receive.
Each type of lawn mower, as discussed in the first post, have different types of blades and sizes, meaning that some require higher maintenance than others.
The level of maintenance will of course affect how well your lawn mower cuts your lawn and ultimately, providing that the blades are kept sharp, will help stop some lawn problems from appearing.
It’s important for us to note at this stage that you can’t just fit any blades from a similar type of machine to fit yours, just because they appear to be a similar size. Only fit the genuine parts recommended by the manufacturer.
If you look at two mowers with similar blades, you will notice that they have the following differences:
- A different total amount of holes on the blades.
- Different diameter holes.
- The distance between the holes will be different.
- The size of the fan curvature may be different.
- A different blade thickness.
- A different blade length.
Although these differences don’t sound important and relevant to the operation of the machine, they do constrain what blades are compatible with your particular lawn mower.
Two Types of Blades
The types of blades available can be divided into two categories; cylinder and rotary, meaning that this technically also falls into the question of which lawn mower you should buy.
If your lawn has a thinner grass type, like a fescue species, cylinder blades will give a very clean cut providing that the lawn is cut quite regularly and not left to grow too long.
These machines can be purchased in various sizes, which obviously determines the size of the blades. 12 to 16 inches is the average size, and is usually sufficient for the size of most people’s lawns. The wider the blade, the less time your lawn will take to cut.
The average machine will usually have 5 of these blades, which is usually adequate for the desired finish. However, 8 – 10 blades can be used to give the absolute finest cut possible, although these amount of blades are normally only used on a professional greens mower.
To make a decision between the blade size (width) and the amount of blades, find the perfect balance between your budget and the amount of manoeuvrability you will have on your lawn as the size of blade system increases.
The blade system must be regularly serviced and sharpened to provide a perfect cut. Some cylinder blades can be sharpened while fitted, where as others have to be removed. Some maintenance companies offer exchange magazine cassettes like in the picture.
Alternatively, if your lawn is a thicker grass type, like a Rye grass, rotary blades are a better option and will provide a stronger cut and avoid the grass from being chewed up by the machine.
These blades also give a cleaner cut for longer grasses as well, so are a good option if you can’t keep the grass as short as you would always like to.
Rotary blade system: The design is very basic. The blade cuts on rotation and the fin on the rear pushes and creates a draft into the collection box. Notice the two rotary blades are different shapes and have a different amount of holes.
When sharpening rotary blades, try to take the same amount off each blade edge with a file, otherwise the blade may become unbalanced resulting in vibration.
Other Mower Blades
Hover Mowers/Mulching mowers and ride-on mowers all use rotary blades as well, therefore the same rules apply when looking at your options. Mulching mowers have static blades inside the underside of the mower to further shred the grass on contact. This system does however prove to be very poor.
Consider the Simple Facts
In summary, considering your lawn’s grass type, availability of time to cut and the amount of manoeuvrability will form the best choice of blades/mower type that you can use.
Return back soon for post number 3 of 6 in this series. (“Should I buy electric powered or petrol powered?”)