When the rotary lawn mower was first designed, manufacturers were yet not aware of how important it was to have the blades of the mower perfectly balanced.
However, they did notice that the engine never lasted through the warranty, and they were forced to do expensive repair work on their own engines.
Research showed that not having the blade balanced at the speeds at which a mower's blades rotate can seriously damage the bearings and the engine of the mower because the unbalanced blades create a destructive vibration.
Why do you need blade balancer
If you wish to maintain your mower yourself, you will certainly need a lawn mower blade balancer, which is a small tool that can help you to ensure that you do not put the blades out of balance.
Remember, the blades in your mower are carefully balanced at the factory, because doing so really helps your engine last longer, and ensures that the manufacturer does not have to engage in heavy repairs on your mower.
So long as your mower runs on it's factory settings, without interference, everything will be fine.
But finally the time comes when your mower's blades are so blunt that it ends up tearing the grass, rather than cutting it efficiently, and instead of your lawn looking neat and trim after your cutting it, it looks rather like some hungry herbivorous animal has been eating at it.
Not only that, but tearing the grass in this way damages it and makes it unhealthy, resulting in unattractive and uneven growth on your lawn.
Preventing this is what you use a lawn mower blade balancer for – it consists of a cone on which you balance the blade after sharpening it.
Now when you sharpen a blade by hand, it is rather inevitable that you will end with one part of the blade of a slightly different weight than the other parts.
How to use lawn mower blade balancer
When you place such a blade on the blade balancer, you will find that the blade tends to lean to one side.
Look carefully to see which of the blades is heavier than the others, and then carefully lessen it's weight by grinding it a little more.
Don't do too much, just take off a little metal and check it's balance again with the blade balancer.
Keep doing this until the blade balances perfectly on the cone of the balancer, without the slightest leaning to one side or the other.
What you have now is a perfectly balanced blade that will run on your mower without ruining the engine or bearings.
However, remember that when maintaining the blade of your mower, you should never try to put a seriously bent blade back into shape – doing this leaves a seam of weakened metal in the blade, and under the torque and other stresses of a running mower, that blade might be so seriously weakened that it actually snaps, causing a serious and potentially fatal injury to anyone who might be in the way.
But for a normally blunted blade, using a lawn mower blade balancer will result in a perfectly reusable blade.