In this video, This Old House general contractor Tom Silva shows host Kevin O’Connor demonstrates the basic parts of a circular saw and how to make clean, straight cuts.
- Always wear safety glasses when using a portable circular saw to protect your eyes from flying sawdust.
- With the saw unplugged, check the spring-loaded lower blade guard to ensure that it rotates back and retracts smoothly.
- There are two basic types of circular saws: gear-driven worm-drive and direct-drive sidewinder.
- Sidewinder saws are available with the blade mounted on left or right side of the saw.
- Be sure to use sharp blades for the smoothest, safest cuts. Carbide-tipped, thin-kerf blades are ideal for making crosscuts and rip cuts in wood.
- Diamond-impregnated blades can cut stone, tile and other masonry materials.
- Fine-tooth plywood blades are designed for producing splinter-free cuts in plywood and other veneer-topped sheets goods.
- Two types of carborundum blades are available: Silicone-carbide blades for cutting masonry, and aluminum-oxide blades for cutting metal.
- To make a crosscut, first mark the cut line onto the board, then align the blade with the line. Be sure the saw blade isn’t touching the board.
- Slide a layout square up against saw shoe, squeeze the trigger and make the cut by guiding the saw along the edge of the square.
- Make a rip cut by first marking a cut line at each end of the board. Then measure the distance from saw blade to edge of saw shoe. This is the offset dimension.
- Measure from the cut line the distance of the offset dimension and draw a line.
- Clamp in place a straightedge board or rip off plywood; place the straightedge on the offset marks, not the cut line.
- Adjust depth of cut to ⅛ inch deeper than the thickness of the workpiece you’re cutting.
- Butt saw shoe against straightedge and make the cut.