How to Properly Sharpen and Balance Lawn Mower Blades

A sharp and correctly balanced lawn mower blade cuts grass more efficiently so you don't have to mow the same area twice. It also cuts more cleanly and evenly, making your lawn look it's maintained by professionals.

You only need to sharpen your blade half a dozen times per year depending on how frequently you mow; the best times are right before you put it in storage, once every several weeks through the mowing season.

How to Sharpen the Blade

To sharpen a mower blade you will need either a bench grinder or a power tool grinding attachment. Dremel makes low priced grinding stone attachments for its popular rotary tools.

1: Before dismantling any part of your push mower or riding lawn mower, make sure the machine is off and blade is still, then disconnect the spark plug for your own safety.

2: Once you have the blade off, place it perpendicular to the spinning grinder and run the blade back and forth to smooth out nicks and chips. Your blade will be made straight but blunt.

3: To sharpen the cutting edge, hold the blade at its bevel angle and run the grinder across the length of the blade. This will restore its nice sharp edge.

Important Note: It's not worth grinding down a blade that has been badly damaged by mowing over rocks and branches. If the blade cannot be restored to moderate condition, replace it.


How to Balance the Blade

Balancing your lawn mower blade is crucial after sharpening. If once side of the blade has more mass than the other, your lawn mower won't run properly and it can cause further damage to the blade and motor.

1: Purchase a lawn mower blade balancer if you don't already have one. This is a cone-shaped tool that balances the blade on its apex.

2: Place the blade on top of the balance and note which side dips toward the ground. This end has more mass than the other end.

3: Lightly grind down the heavier end of the blade and rebalance it. If one side is still heavier than the other, grind some more, otherwise you are finished.


© Had2Know 2010