A circular saw is one of the most common power tools in use today. With the appropriate blade, circular saws are capable of cutting wood, steel, masonry and ceramic tile. Learn how to find the circular saw design and features that will make your projects a success.
Circular Saw Basics
Circular saws make quick, straight cuts across a board (crosscuts) or along the board's length (rip cuts). You can also set a circular saw to make bevel cuts. Standard components on a circular saw include:
- A blade guard that covers the blade when the saw is not in use and retracts to expose the blade during use
- A foot plate or shoe that steadies the saw against the work piece
- A depth adjustment to allow for work pieces of different thicknesses
- A bevel adjustment that lets the foot plate tilt in relation to the blade for making bevel cuts
Circular saw sizes are usually classified by the diameter of their blades. Sizes of 5-1/2 to 7-1/4 inches are the most common. There are also many options available on circular saws. Choose your saw based on your specific needs.
When choosing your saw, you'll have two basic designs to choose from:Sidewinder Saws
Worm Drive Saws
Sidewinder or inline saws are the most common, traditional circular saws. The motor is located along the same axis as the blade. A shaft runs directly from the motor to drive the blade. Sidewinder saws are more compact and lightweight than worm drive saws and are well-suited to most circular saw applications.
Worm drive saws have their motors positioned at a right angle to the saw blade. The motor uses gears to increase the torque transferred to the blade, which makes the saw well-suited for heavy-duty use. Worm drive saws are longer than sidewinder saws and tend to be quieter.
Always follow the device manufacturer's operating, maintenance and safety instructions, including instructions on safety gear.
Circular Saw Power Sources
Where and how you use your circular saw will help determine the power supply you need. Two types are available:Cordless Circular Saws
Corded Circular Saws
Cordless circular saws are convenient when working in areas where extension cords are difficult to use. And, since they are smaller than most corded saws, they work well in confined spaces. Cordless saws are best suited to cutting wood and wood products, due to the limitations of their batteries. They can cut tough materials, but the extra power needed for those applications drains batteries quickly. Cordless saws typically range in size from 5-3/8 to 6-1/2 inches.
Corded circular saws don't depend on batteries for power and are better suited for tough cutting jobs like masonry, steel and continuous woodcutting. Corded saws are available in many sizes, but the most common is 7-1/4 inches. A corded circular saw requires a suitable extension cord. Follow the device manufacturer's recommendations for compatible extension cords and see Power Cord Safety Tips.
Circular Saw Features
Once you've decided on the design and power source, compare the features:
- Amps on corded saws and volts on cordless saws measure power. Higher amps and volts mean more cutting power.
- Blade capacity determines the maximum depth of cut a saw can achieve. The larger the blade, the deeper the cut. The most common blade diameter is 7-1/4 inches. Most saws with blade capacities of 6 inches or more can cut through 2 inch dimensional lumber at a 45 degree angle in a single pass. A 5-3/8-inch saw can cut through 2 inch dimensional lumber in one pass at 90 degrees but requires two passes at 45 degrees. As a general rule, saws with smaller blade capacity weigh less and are easier to control.
- Electric brakes reverse the flow of electricity in the saw motor when the trigger is released. Reversing the current stops the blade's momentum quickly. Electric brakes can stop the blade in as little as two seconds, much quicker than a blade on a saw without this feature.
- Spindle or shaft locks make it easier to change the saw blade. The shaft lock immobilizes the shaft and blade, making it much easier to change the blade.
- Bevel capacity indicates the maximum bevel cut the saw can make.
- Bevel stops are presets that allow quick adjustments for bevel cuts.
- Laser guides help improve cutting accuracy by projecting a beam of light onto the work piece.
Shop for Circular Saws
Always unplug corded power tools and disconnect the battery on cordless power tools when servicing them.
Circular Saw Blades
A key part of the saw is the blade. Different blades are available for different applications. When purchasing a blade, make sure it's compatible with your saw. Some common blade types are below:
- Steel blades are inexpensive and work well for cutting softwood; however, they dull quickly in hardwood.
- High-speed steel blades are harder than steel blades and stay sharper longer.
- Carbide-tipped blades have carbide tips attached to their teeth. They are more expensive than other blades, but they stay sharp much longer than steel or high-speed steel.
- Tile-cutting blades are specially designed for cutting ceramic tile. Better tile-cutting blades have diamond-tipped blades.
- Masonry blades are made of abrasive material for cutting concrete, brick, cinder block and other masonry materials.