Get to Know Your Lawn Mower Blade Types
Mower blades come in a variety of shapes and sizes. Maybe you’ve been curious as to why that is? The reason for the variety in sizes probably doesn’t warrant too much explanation. But, for those curious about the reasons why their mower blades look like they’ve been beaten into unintelligible shapes, here’s why: your various lawn mower types have different aerodynamic functions, and they’ve been designed for different applications.
- Deck Blades: Your standard blade that produces a suck and cut effect.
- Low Lift Blades: Ideal for side discharge on areas that contain a lot of sandy soil
- High Lift Blades: Provide better suction that works well for bagging applications. Also helps with longer, more compact grass.
- Mulching Blades: The purpose here is pretty self-explanatory; the design makes it possible for the blade to recycle clippings through the blade’s path and then return them to the soil.
- Specialty Blades: These come in yet even more shapes that have generally their purpose printed on the box they come in.
What Lawn Mower Blade Types Do You Need?
Before really trying to understand the various lawn mower blade types, it’s helpful to know how a lawnmower cuts grass in the first place.
We’ve talked about this subject in greater detail in a previous article, but the salient points are these: for a blade to be effective at cutting a relatively flimsy blade of grass, it needs to be able to pull the grass up into its cutting path. It also needs to provide resistance on both ends of the grass so that the mower blade doesn’t simply slap the grass back down to the soil uncut.
To achieve this, blade manufacturers have borrowed and tweaked a design from aviation. Much like the wing of an airplane harnesses wind resistance to provide lift, a lawn mower blade has an uptick at the back of the blade to pull air up through it. The grass follows, standing up for the blade with the suction providing some resistance on both ends of the blade of grass. This allows the mower blade to actually cut.
Of course, different angles of upturn at the back of the blade produce different results, and those results can be better tailored for different applications.
Standard or Deck Blades
Sometimes referred to as 2-in-1 blades, standard blades probably get the most use in the lawn trimming game. For the most part, these blades have an aerodynamic design that causes less strain on the engine that has to turn it. The front cutting edge remains flat, and their back edge has a slight upturn that generates a continuous “suck and cut” action.
Because these mower blade types provide great lift in one direction, they’re good for side discharging and bagging applications.
Low Lift Blades
When you’re trying to provide enough lift for the blade to cut your grass, but not so much that your super sandy lawn gets pulled up into the deck also, the low lift blade will be your friend. Here’s why: with a smaller uptick at the back of the blade, they provide less lift than your other mower blade types.
They won’t do as good of a job cutting your beefier grasses as a blade that produces a ton of lift, but they also don’t kick up as much dust. Also, because they produce less drag, they’re easier on your fuel consumption as well as the wear and tear put on your engine.
High Lift Blades
With a more dramatic upturn at the back of the blade, the high lift mower blade produces much more lift. Because it produces so much lift, this type will require a more powerful engine to work well. And, it can cost you a bit more in fuel to use it. But, it generally results in a better cut in thicker grasses. It’s an ideal choice for when you’re bagging up your clippings since the improved lifting force can rocket the clippings up and out of the deck.
The mulching blade has a more unique design than your deck and lift blades. Rather than employing a relatively straight cutting edge with a swoop in the back, the mulching blade kind of looks like it swoops all over the place.
This design allows your mower to suck the grass upward to be cut, then the clippings are recycled around the deck to get chopped up even more. The middle part of the mulching blade, the weird bit, is designed to send the nutrient-rich, fine-cut clippings back to the ground where they can feed the soil.
You can still bag or side discharge with a mulching blade if you prefer, however, these blades don’t provide as much lift as your standard blades. They also perform much better with maintenance cuts than overgrown grass.
Then you’ve got you blades that kind of do their own thing. Take the Arnold Power Rake, for example. You can choose to mulch and bag with it (though there are better options if that’s all you’re looking to do), but this mower blade’s purpose is primarily to rake, dethatch, and scalp your lawn.
Or, take Honda Commercial‘s MicroCut Twin Blade System from their HRC line. It uses two blades stacked on top of each other and offset. In this instance, the blades themselves don’t have a terribly unorthodox design, but there are two of them. The idea here is that you get a cleaner cut and finer mulching performance since there are two blades cutting into the grass clippings as they circulate under the deck.
Choosing Mower Blade Types
In any case, when it comes to selecting your mower blade types, it’s best to keep in mind your particular application. Do you plan on bagging up your clippings or leaving them in the yard? What sort of lawn conditions are you working with? Is your grass thick and overgrown or patchy and sandy? Are you trying to win awards for the best lawn, or you just trying to get the lawn mowed before the neighbors complain? Knowing the differences between the various lawn mower blade types will help you achieve the type of cut that works best for you.