The Saw
Behind the panel The Saw · series D, Tools Through Time.
The saw is the tool that turned forests into standard lumber, and standard lumber is what made fast, cheap building possible.
How a saw cuts
Each tooth is a small cutting edge. Teeth are "set", bent alternately left and right, so the cut (the kerf) is wider than the blade and the blade does not bind. Rip teeth, filed straight across, act like chisels to cut along the grain. Crosscut teeth, filed at an angle, act like knives to sever fibres across the grain. Western saws cut on the push; Japanese saws cut on the pull, allowing thinner blades.
From pit to mill
Before sawmills, logs were sawn by hand in saw pits, one sawyer above and one below. Water-powered mills brought reciprocating saws, and the circular saw followed; in the United States, Tabitha Babbitt of the Harvard Shaker community is credited with an early circular saw around 1813. Steam power and band saws made lumber plentiful and dimensioned, the basis of balloon framing.
Portable power
In 1924 Edmond Michel and Joseph Sullivan founded the company that sold the Skilsaw, a portable electric circular saw that brought mill power to the job site. Worm-drive and sidewinder saws, table saws, miter saws and cordless tools followed.
Safety
Saws are among the most dangerous tools in construction. Guards, riving knives, push sticks, eye and hearing protection, and training reduce kickback and contact injuries. Flesh-sensing technology that stops and drops a table-saw blade on contact was introduced in the early 2000s.
In the shop
Carpentry, cabinetry and drywall students use handsaws before power saws, because understanding the cut makes a safer operator.
