Circular saws are the workhorse of the carpentry world. Their invention revolutionized the industry and allowed contractors to build a house in a third of the time required with the old manual saws. Circular saws also opened up carpentry to do-it-yourself types who just did not have the time or energy to do large projects manually. From framing to finish work, the circular saw can do it all with a quick change of the blade. To change a blade, all you need is a couple of tools and a few minutes for this simple procedure.
Disconnect your saw from any power sources and lay the power cord onto your work bench. Set your saw onto the work bench with the blade hanging off of the side. Hold the saw securely to the bench by the operating handle.
Open the blade guard and hold it open with the thumb of the hand you are holding the saw handle with. Rotate the blade by hand to line up the offset hole in the blade so that it is pointing toward the floor. Slide your drill bit through the offset hole in the saw blade so that it is halfway through. Rotate the blade clockwise until the drill bit is resting against the saw frame, preventing further rotation.
Twist the bolt holding your blade in a clockwise direction to loosen and remove it. This is the opposite direction that you would normally loosen a bolt, but, these blades are held with a left-handed thread bolt to prevent blade loss during operation. Remove your drill bit and set it aside. Remove the old blade and set it aside.
Slide your new blade onto the hub and twist on the retaining bolt. Remember that it is left-hand threaded, so to install it you will need to twist it counterclockwise. Slide your drill bit through the offset hole in the blade and rotate the blade counterclockwise to until the bit rests on the frame. Tighten the bolt completely by hand. Use your adjustable wrench to twist the bolt firmly into place.
Remove the drill bit from the offset hole. Plug your saw into a power source and cut some wood.