Tips for Sawing Curves and Irregular Lines

Unlike most blades for cutting straight lines, a blade for cutting curves or zigzagging, irregular cuts must be narrow in shape and used in an almost straight up-and-down position. Four saws for cutting curves are discussed in this article: the keyhole saw, coping saw, saber saw, and band saw. The first two are very inexpensive handsaws. The saber saw is one of the most versatile electric tool and the band saw is an expensive shop tool. All four use replaceable blades.

Keyhole Saw

Also known as a compass saw, the keyhole saw is typically used in making irregular or curved cuts and in starting cuts in the center of a board or panel from a small drilled hole. Blade lengths vary from 10″ to 14″. The blade is pointed at the “toe” (tips) and is less than an inch wide at the “head”.

The handiest type to buy comes as a kit, with three interchangeable blades: one cuts broad curves or straight lines rapidly; one saws tight curves, zigzags, and cutouts; and one cuts metal. The last blade, for metal cutting, is what makes the package a bargain; it saves the additional expense of buying a hacksaw.

When cutting curves with the keyhole saw, cut perpendicular to the surface. Be careful with the blades; they tend to bend easily. To begin a cutout, insert the blade in a previously drilled hole. Once you’ve started a long, straight cut, you can insert a regular handsaw in the cut to finish the job quickly.

Coping Saw

With its thin, wiry blade held taut in a small rectangular frame, the coping saw makes thin, accurate cuts and follows tight curves with ease – but cutting is limited to surfaces that its relatively small frame will fit around.

Both wood and metal cutting blades can be used in a coping saw frame. For inside cuts, slip the blade through a pre-drilled hole and then reattach it to the frame. When cutting vertically through material held in a vise, point the teeth toward the handle and cut on the pull stroke. If you’re working on something supported horizontally, as on a sawhorse, o\point the teeth away from the handle and cut on the push stroke.

Saber Saw

Though a keyhole saw kit will get you through almost any basic curve cutting, a saber saw makes cutting curves – and, in fact, almost any cutting job – painless.

The saber saw has a high-speed reciprocating motor that drives any of several interchangeable blades to cut wood, sheet metal, plastic, rubber, leather, and even electrical conduit. Depending on how you use it, it will cut intricately curved lines, circles, straight lines, and bevels. It can even make a cutout in the center of a panel without a previously drilled starting hole.

Remember to cut with the material’s good side down; the upward-cutting blade may fray the top surface as it cuts. For more instructions on proper use, see the owner’s manual provided with the tool.

Band Saw

This power saw has a continuous band-like blade that rolls between two wheels – one above and one below the cutting platform. A narrow blade can make very tight circular cuts, and a wider, sturdier blade can cut wood over 6″ thick. Because the saw is fairly specialized, you probably won’t need one for making bookshelves and cabinets – except perhaps for cutting intricately curved decorative pieces.