Unplug the grinder from the wall. Rotate the blade with your hand while pressing down on the locking mechanism. When the button compresses and the blade stops moving, you have locked the blade in the stopped position. Continue holding the button down.
Loosen the nut securing the grinding wheel to angle grinder by turning it counterclockwise. Pull the grinding wheel off the drive shaft.
Insert the wood cutting blade onto the drive shaft, making sure the blade's teeth are in the direction of rotation of the grinder.
Secure the blade to the grinder with the removed washer and nut. Tighten the nut with a wrench.
Put on chainsaw protective pants and safety glasses to protect your body. Hold the grinder firmly in both hands.
Insert the cutting blade of the grinder slowly into the wood surface while maintaining the blade position. If the blade is tilted off center to the cut line the grinder will kick back and may injure you.