How to Balance Mower Blades
- 1). Wear safety glasses whenever operating any machine that removes metal from an object. Put on gloves if you are uncomfortable handling the metal blade.
- 2). Grind the ragged edges of the lawn mower blade under the grinding wheel. Keep the original cutting angle to the face of the blade.
- 3). Remove as little of the blade metal as possible. Dip the end of the blade frequently into cold water. Keep the end of the blade cool.
- 4). Alternate ends of the blade while grinding. Make two passes on one end of the blade, dip into the water and make two passes on the other end. Continue to work the cutting edges evenly. When the blade shows a sharp edge, balance the blade.
- 5). Slip the 1/2-inch diameter rod through the main shaft hole on the blade. Hold the rod as level, or horizontal, as possible.
- 6). Steady the blade so the ends sit at the 3 o'clock and 9 o'clock positions. Release the blade. If the blade deflects down, that end is heavier.
- 7). Remove a small amount of metal from the backside of the cutting edge on the blade that is heavier. Retest for balance. A balanced blade will keep its position, 3 o'clock and 9 o'clock, on the horizontal rod.
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