What Happens If Mower Blades Are Dull? (Solved & Explained!)

Dull blades are definitely not good for your lawn. They tend to rip out, rather than evenly cut your grass and when it’s torn like this, then browning is soon to follow after you’ve finished mowing. Sharpen your blades every 20 to 25 hours of use or weekly if you are doing commercial mowing — It ensures that your mower is always cutting cleanly and evenly!

In today’s article we’ll tell you all about lawnmower blades and sharpening based on the most commonly asked questions online. Let’s take a look at what you need to know about your mower blades!

What are the signs of a dull lawn mower blade?

If the grass you are cutting looks torn, rather than cleanly cut, then the blade is definitely dulling. Other signs include your mower cutting at uneven heights and when inspecting the blades, if you see any nicks or other signs of damage then it’s definitely time to sharpen the blade.

How do I know if I need new lawn mower blades?

Typically, you will want to replace your blades once a year, but occasional damage from rocks and other items accidentally mowed may require replacement blades if sharpening proves ineffective. If your mower is cutting unevenly, check for damage on the blades – small dent and nicks can often e fixed with sharpening, but if the damage is extensive then new blades are a better option.

When Should lawn mower blades be replaced?

Lawnmower blades needs to be replaced annually for best results, or if you are using them professionally then twice a year will give you optimal performance. With regular sharpening and balancing you can extend the life of the blades but eventual wear and tear will warrant the need to regular replacement to get the best results.

How do I know if my lawn mower blade is unbalanced?

If you are needing to push the mower slower than you used to in order to get good, even cutting, then this is one sign that the blade is imbalanced. Additionally, the mower is going to vibrate more with an unbalanced blade, so if you experience either of these then it’s time to check your blade up close to see if it’s imbalanced.

How do I know if my lawnmower blade is sharp?

If you are seeing bends in the blade, dents, or nicks, then it’s definitely time to sharpen the blade. You can also simply check the edge by touch – it should not be very sharp, but a butter-knife thinness and edge on the blades is just about perfect. Anything sharper makes for a thin blade that is less resistant to damage during normal operation.

Should a lawn mower blade be razor sharp?

No. Your lawnmower blades are moving very fast, sometimes up to 4000 rpm, and a razor-thin blade is likely to chip quite easily the first time that you encounter something tough in the yard.

Keep the edge the same as a kitchen butter knife and you’ll have the perfect mix of high-speed cutting power with added durability for those occasional things you didn’t mean to run over with the mower.

How do you sharpen a lawn mower blade without removing it?

If you want to sharpen the blades without taking them off, you would first need to place the mower on a wooden block to keep it accessible and firmly in place, and after this you want to clean the blades with a steel brush and a little water. After that, simply do the sharpening with an angle grinder and you can sharpen the blades without removing them.

How much does it cost to sharpen lawn mower blades?

This really depends on the lawn mower. A standard push mower might only cost $5 – $15 per blade, but higher end and larger mowers, such as rider mowers, could range anywhere from $20 – $60 for professional sharpening services.

How long does a mower blade last?

If you are sharpening the blades every 20 to 25 hours of use, then you can generally expect an operational lifespan of approximately 100 – 200 work hours with your blades. Some higher end blades can give you much better performance, often in the neighborhood of 400 hours of operation – sometimes those ‘fancy’ blades are well-worth the cost!

How much does it cost to replace a lawnmower blade?

It depends on the blades, but by way of example Riding mower blades typically range between $10 to $40, while Zero-turn blades might set you back between $12 and $31 dollars. By contrast, standard Gator mulching blades may be found for around $30 and while regular push mower blades might be anywhere from $10 – $40, depending on your mower.

Are new lawn mower blades already sharpened?

Yes! When you get a new mower, the blades will always be sharpened and ready to go, courtesy of the blade manufacturer. There is no need to sharpen the blade on your new mower until you have used the mower for approximately 20 to 25 hours of mowing time.

How do you sharpen blades on a reel mower?

You can sharpen a reel mower at home with files, just keep in mind that it will be a bit time consuming. Just pay attention to the existing cutting edge and don’t sharpen it too thin – you want a thinness equivalent to a butter knife so that the blade cuts effectively but still remains durable.  

How often do you sharpen reel mower blades?

If you are using the reel mower for commercial jobs, then once a week is going to be the recommended frequency to keep your blades at their best. If it is only for personal use, however, then you can get away with sharpening the blades every 20 to 25 hours of use.

Can you sharpen a mulching blade?

Yes, you can easily sharpen a mulching blade. Due to the extra edges that you get on a mulching blade, as opposed to a standard blade, you may need an assortment of files in order to effectively sharpen the length of the blade.