Sharpening Lawn Mower Blades

Lawnmower blades play an important role in not just keeping your yard look nice, but also keeping your lawn healthy. Nice looking lawns say a lot about yourself and give people a good impression. Sharpening your lawnmower blades is a simple task and can be accomplished with a couple of tools, jack, and jack stands. This guide will include general materials needed, removal of the blade, and the sharpening process.

Supplies:

Tools for removal (vary between lawn mower models and brands) and choice of tool for sharpening. Tools generally needed are a socket, ratchet, file or grinder, wire brush, and a jack with supports.

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Step 1: Lifting the Mower for Blade Access

Before we get started I want to state that removal of the lawnmower blade will vary between different brands and models of mowers. Today I will be working on a riding lawn tractor with two blades.

First thing I want to do, is set the park brake and lift the front of the mower so I can access the blades under the mower deck. This can be accomplished in many ways such as using a mower jack, using a floor jack and jack stands, or driving the mower up on top of boards or ramps. Today I chose to use a mower jack because I had access to it.

Step 2: Mower Blade Removal

Once the mower is lifted high enough so I can access the blades. Now start the removal process. First, I need to find the appropriate size socket and impact wrench that will fit the fastener that attaches the blade to the spindle. A tip to help is the nut holding the blade on can be rusty or covered with hard mud and grass. With that take a straight screwdriver or wire brush and clean around the nut so the socket or wrench will fit securely without damaging the nut from slipping. Using a lubricant, such as WD-40 can help rusty fasteners break lose. Now use the impact wrench to break the nut or bolt loose. Use a wrench or breaker bar but that route will require help from a friend to prevent the blade from turning.

Step 3: Blade Sharpening

After the blade is removed, I would check for sever wear or severe bending. If that’s all good than the sharpening process begins. For this process use a bench grinder, grinder, file, drill with stone wheel, or other. I chose to use a bench grinder. When I sharpen the blade I do not want to create a fine edge like a knife but more like a wedge-style cutting edge. The wedge style of sharpening is much stronger and will not damage as easy, as the knife style sharpening will. The wedge is a sharpening on the top side of the blade and is a cutting angle of sixty degrees.

Step 4: Finishing Up With Installment of the Blade

At last, after the blade is sharpened it is now time to reinstall blade with all the appropriate fasteners. Be sure the blade lift points are on the top and not on the bottom facing the ground. One blade is mounted, torque to manufacture specs and then lower the mower down. Drive to a safe place to start the mower to check for noise or vibration of a blade installed incorrectly. I hope this helps your lawn look and grow nicer!

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