Can You Sharpen Lawn Mower Blades Without Removing Them?

If you've got uneven patterns in your lawn, or find that mowing is taking up more time and effort than it used to, the chances are your blades need sharpening. While it is safer and typically manufacturer-recommended to achieve a better finish by removing the blades, it is possible to sharpen them without doing so. The main reason you'd do this is if you're short on time, tools, or both.

The first step to sharpening your mower's blade while still attached, is to gather the necessary tools. While bench grinders and sharpening stones will make light work of the task, it's possible to achieve a fine result using simply a hand file, or even just sandpaper. Regardless of the tools at your disposal, be sure to wear thick gloves and protective eyewear, as plenty of dirt and debris will be kicked up during this process. To begin, place your mower on its side, and be sure to steady it with a wooden block or similar. Secondly, clean the blades with a thick-bristle brush — this will make the sharpening process much quicker and easier. Now, take your blade grinder, sandpaper, or hand file, and begin sharpening the blade from the outer edge. Work inward until you're pleased with the result and repeat this for both sides of the blade. It sounds easy enough, and it is, but there are some key factors to remember while sharpening your mower's blades in situ.

The first thing on your mind with a task like this should always be safety. We've already established that you should be wearing thick gloves and protective eyewear from the get-go, as the very nature of this job requires you to work in very close proximity with blades. Before beginning, you should also be sure that the mower is unplugged if electric or have an empty tank if it's a gas-powered mower. We're not here to have the electric vs gas lawn mower debate, but regardless of your preference, be sure there's no chance of it firing up (or spilling anything) when working on it.

Once sharp, you'll ideally want to keep your mower blades in great shape for as long as possible. One way to ensure this happens is to inspect any area you intend to mow first. If there are rocks, wood, or any other solid items on the lawn, be sure to clean the area up as best as you can before mowing. This is because solid objects will blunt the blades quicker, and you'll find yourself donning the gloves and glasses far quicker than you'd like if you're mowing cluttered grass. Also, one of the common lawn mower mistakes it to store it outside, so be sure to keep your mower clean and dry. This is because the metal blades are susceptible to corrosion, and a rust-damaged blade won't be as effective as it should be. Storing your mower in a dry shed, or under a watertight tarp, will help to keep the blades in good shape for longer.