Home Depot Lawn Mower Blade Balancer. Hold the blade in one hand and turn the socket wrench counterclockwise and bring out. Replace oem & other cross references.
When you this, the lawn mower will not suddenly turn on. However, it's easier to keep the correct angle using a flat file. Remove the blade from the mower;
Now turn the lawn mower upside down.
It will fit blades up to 3.5 inches wide and mounting hole up. No need to mount anything on a wall or in your shop. 1 ea fits riding mowers, lawn tractors. The blade balancer is fairly small and lightweight, yet sturdy enough to handle the weight of the mower blades.