Circular saws
A circular saw runs a straight cut through timber, plywood and laminate board faster and more accurately than any handsaw. Blade diameter sets the cutting depth, and tooth count decides whether the cut comes out fast or clean. A brushless motor lasts longer, runs cooler and pulls more cuts out of the same battery. Cordless saws are often sold as a bare tool without a battery, so it pays to check the manufacturer's platform.
Circular saws
A circular saw runs a straight cut faster and more accurately than any handsaw, which is why it belongs in every workshop's basic kit. It suits shortening studs and cutting plywood, OSB boards and laminated panels to size. Mains models run with no time limit, cordless ones manage without an extension lead and earn their keep on site as much as in the garden. Many cordless saws are sold as a bare tool without a battery, which works out cheaper for anyone who already has a platform at home.
Blade diameter sets how deep the saw reaches, and it is quoted together with the maximum cutting depth at a right angle. A 150 mm blade manages around 50 mm, the usual 165 to 190 mm reach 55 to 70 mm, and machines with a 235 mm blade go through a stud as well. Smaller saws are lighter in return and steer better one-handed. Along with the diameter comes the arbor bore, most often 20 or 30 mm, which has to fit the spindle.
Cut quality is decided by tooth count, chosen to suit the material. A blade with twenty to forty teeth cuts fast and rough, which suits solid wood and construction timber. Blades with sixty teeth and more advance more slowly but leave a clean edge on laminate, plywood and veneered boards. Teeth with brazed carbide tips last many times longer than plain steel teeth.
A brushless motor has no carbon brushes to wear down, so it lasts longer and runs cooler. On cordless saws it also pulls noticeably more cuts out of the same battery than a classic commutator motor. The battery is bought to match the manufacturer's platform and is not interchangeable between brands. With offers labelled without battery it therefore pays to check which system the tool belongs to.
Cutting depth is set so the blade sticks out only three to five millimetres below the workpiece, which lowers the risk of kickback and of tearing the underside edge. Tilting the base plate up to forty-five degrees allows a mitre cut, while a rip fence or a guide rail keeps the saw on line. The lower blade guard has to spring back freely into the closed position, and the extraction port takes most of the sawdust out of the kerf.