Buying Guide for Circular Saws

Circular saws are 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. Circular saw sizes are usually classified to by the diameter of their blades. Sizes range from 3" to 16", but 5 3/8" to 7 1/4" are the most common. There are also many options available on circular saws. Choose your saw based on your specific needs.

Design Variations
When choosing your saw, you'll have two basic designs to choose from:

• In-Line Saws are traditional circular saws. The motor housing sits perpendicular to the blade. A shaft runs directly from the motor to drive the blade. In-line saws are well suited to most circular saw applications and are the most common.
• Worm Drive Saws have their motor housings positioned parallel with 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.

Power Source
Where and how you use your circular saw will effect the power supply you need. Two types are available:

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 range in size from 5 3/8" to 6 1/2".

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".

Features
Once you've decided on the design and power source, compare the features:

• 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". Most saws with blade capacities of 6" or more can cut through 2" dimensional lumber at a 45° angle in a single pass. A 5 3/8" saw can cut through 2" dimensional lumber in one pass at 90° but requires two passes at 45°. 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, compared to up to twelve seconds for a saw without this feature.
• 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.

Blades
The most important part of the saw is the blade. Different blades are available for different applications. Here are a few common blades and their uses:

• 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 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.