Can You Sharpen Lawn Mower Blades Without Removing Them From The Mower?

If your lawn looks ragged after mowing and the clippings are a soggy mulch, there's a good chance that blunt lawn mower blades are the culprit. The good news is you don't have to take them off the mower to sharpen them. However, the operation could be dangerous if the blades accidentally spin up while you have your hands in there, so it's important to follow basic lawn mower safety tips.

One of the best times to sharpen your lawn mower blades without removing them is right after you have given the machine a thorough cleaning. If it's a gas model, you will need to empty or seal the tank and disconnect the spark plug. If it's electric, unplug it or remove the battery. That way, there's no danger of the mower starting up unexpectedly so you can safely turn it over and get to work. 

Block up the mower so it is stable while you work. If the blade is clean, the cutting edges should be obvious even when they are blunt. Take a 10-inch metal file and apply firm pressure on the forward stroke. Don't drag because the teeth don't work backward. Lawn mower blades shouldn't be razor sharp, so about five to 10 minutes of work on each cutting edge should restore it. Then, take a brush and clean up any metal shavings left behind. 

If you can move the mower within range of a power outlet or you have cordless tools, then you can use a machine instead of a hand file. This can be a lot quicker, although you'll need to be a little more careful. Wear gloves and safety glasses or goggles while you work.

Using an angle grinder with a metal-cutting blade is one popular solution. In experienced hands, it will remove metal rapidly and can sharpen a blunt mower blade very quickly. However, these are powerful, noisy tools and some people find them difficult to manage, which could be dangerous, especially if space is limited underneath a small mower.

The other option is a rotary tool from your collection of home improvement gadgets. Rotary tools are much lighter and more manageable than an angle grinder and have attachments available specifically for sharpening. They don't cut metal quite as aggressively, but they will allow you to sharpen your lawn mower blades almost effortlessly without removing them from the mower. Whichever machine you choose, don't forget to clean up the waste.