Crosscut saw

A crosscut saw (thwart saw) is any saw designed for cutting wood perpendicular to (across) the wood grain. Crosscut saws may be small or large, with small teeth close together for fine work like woodworking or large for coarse work like log bucking, and can be a hand tool or power tool.

The cutting edge of each tooth is angled in an alternating pattern. This design allows each tooth to act like a knife edge and slice through the wood in contrast to a rip saw, which tears along the grain, acting like a miniature chisel. Some crosscut saws use special teeth called "rakers" designed to clean out the cut strips of wood from the kerf. Crosscut saws generally have larger teeth than rip saws.

Some saws, such as Japanese saws and those used by the ancient Egyptians, are designed to cut only on the pull stroke. Western saws, on the other hand, are designed to cut on the push stroke.

Many crosscut saws have a wooden handle with the return edge at right angles to the un-toothed edge of the saw blade, allowing the saw to serve as a square for marking material to be cut at a right angle.

Larger saws used for forestry and logging work include both one-man and two-man saws, and both bucking and felling saws. A bucking saw generally has a straighter back and less of a pronounced curve on its cutting surface. Since bucking saws are more often used on trees that are already downed, the greater stiffness and weight aids swift cutting, and allows two-man saws to also be used by one person, pushing as well as pulling.

A felling saw is generally less stiff than a bucking saw and the backside, as well as the cutting side, is usually curved inward. Felling saws are more often used to cut down standing trees, so the thinner, lighter design is easier to use without gravity holding the blade against the cut. The concave back of the saw makes it easier to place wedges, preventing the from closing on the saw.

...
Wikipedia