Safety tips for circular saws
Just about every construction site in this country has at least one circular saw – if not several – in use at some time. That means just about every construction worker is familiar with the sight, sound and feel of one, but not every worker knows how to use circular saws safely.
The basic circular saw types are:
- 5-inch trim circular saws – Blades are usually on the left side of the motor to maintain a line of sight to the work for right-handed users. Used for smaller jobs, there are many cordless models available.
- 6½-inch circular saws – These saws are suitable for cutting and ripping lumber and sheet goods to size, but are usually not considered heavy-duty and have limited cutting capacity, especially when cutting bevels.
- 7¼-inch circular saws – The most common circular saw in the construction industry, they can cut lumber up to 2¼-inches thick and are powerful enough to cut a variety of materials, including composites, concrete, and ferrous and non-ferrous metal sheeting with the appropriate blade.
- 8- and 10-inch circular saws – Considered specialty saws, these are heavier and more cumbersome because they are designed to cut timbers and lumber up to 4 inches thick.
- Worm-drive circular saws – These saws have a worm-drive gearbox and the blades are left of the motor.
To use the saw effectively – and keep your fingers and other body parts safe – always do the following:
Familiarize yourself with the circular saws you are going to use. Make sure you know how to use the bevel and depth adjustments and that they are working freely and lock securely.
Make sure the blade is appropriate for whatever material you are cutting and is fastened securely. Check that the lower guard moves freely and springs back to the closed position with no obstructions.
Check the power cord for any loose connections, exposed wires or other damage.
Analyze the cut
Use the appropriate supports, such as sawhorses or blocks of wood to raise the piece to be cut off the ground at least far enough for blade clearance and a comfortable cutting position. Make sure the piece will not bind the blade (excessive knots or pitch can cause kickback, cutting in between the supports so the piece “pinches” as you cut).
Avoid cutting small pieces that can’t be properly secured and on which the base plate can’t properly rest. Adjust the blade so that less than a full tooth is visible below the material you are cutting (⅛ to ¼ inch greater than the thickness of the material).
Make sure you will be able to keep your hands and body away from and to the side of the saw throughout the entire cut without overreaching. Saw so the larger part of the base plate will be supported throughout the cut and you won’t have to support the saw’s weight as the severed piece falls away.
Make the cut
Line up the appropriate sight line notch with the mark where you want to cut the lumber. Keep the blade away from the material and pull the trigger.
Allow the blade to come up to full speed before carefully pushing the saw into the piece. Keep your eyes on the guide/front of the blade all the time. This keeps you looking forward along the marked line and out of the way of flying sawdust. Make sure the base plate remains flat on the piece.
Push – but not too hard. A sharp blade should cut most materials with minimal effort. If the motor seems to slow down you are pushing too hard and risk binding the blade and causing kickback.
Make sure the guard snaps back. As you exit the cut, you should be able to feel – and maybe hear – the lower guard return to its position. Even saws in the best condition will have guards that bind if debris from the cut becomes lodged in the mechanism.
Never remove the saw from the piece while the blade is spinning. When making a partial cut or repositioning during a cut, wait for the blade to come to a complete stop before removing the saw from the piece. When starting up again, center the blade in the kerf and make sure the teeth are not touching any part of the material before pulling the trigger.
Keep the saw away from your body and do not set it down until the blade stops spinning. You can release the trigger just before the blade completes the cut so the remaining material will slow the blade and minimize “coasting,” which is safer and saves a little time waiting for the blade to stop.
–by Rob Fanjoy