Stay on Guard Against Kickback
Kickback causes and strategies
All spinning saws can kick back. And, boy, does it happen quickly! To protect yourself, learn the causes of kickback, and counter them with safe work habits. You'll reduce the chances of kickback happening-and if it does, you'll be out of harm's way.
Pinching is the most common culprit. If the saw kerf closes in on the blade so that it can't spin freely, something has to give. Depending on what kind of tablesaw you're using, either the tool jumps or the wood flies in the direction of the saw blade's rotation.
On a tablesaw, the wood's direction is straight back at you. On a radial-arm saw, it's straight at you when ripping and away from you when crosscutting. When using a handheld circular saw or a chainsaw, the saw itself can leap toward you.
Always stand slightly to the outside edge of the board when you're ripping on a tablesaw. That keeps you out of the direct line of kickback. If you're feeding the workpiece by hand, your hand can slip forward toward the blade when the board kicks out. So use a pushstick made of soft plastic, or a properly shaped piece of wood, and keep it out of the blade's path. Don't pull the workpiece from the back side of the tablesaw-a kickback can yank your hand right into the blade.
To avoid tablesaw kickback, keep the kerf open with a splitter-either a commercial version or one built into a homemade table insert. Most tablesaws also come with anti-kickback pawls, those metal teeth that prevent the workpiece from sliding backward. Keep them installed on the saw. Make sure each piece of wood, whether it's a long board, wide sheet, or something in between, has adequate support all the way through the saw blade. When making a bevel cut, keep your miter gauge or pushstick on the opposite side of the blade's high point.
When you're using a radial-arm saw, again, don't stand in line with the board when ripping. Keep your hands out of the line of cut at the infeed side, and don't reach around the blade.
Be patient with portable saws
Kickback often occurs when you're cutting large sheets of material. If you let the sheet sag down, the kerf can close and pinch the blade as you near the end of the cut. Keep your hands and body to one side of the line of cut. Always maintain a firm grip on the saw. And don't stretch so far over the workpiece that you're left in an awkward, unbalanced position.
Remember, too, that big sheets need wide, solid support all the way around, in the form of a workbench or well-made stand with rollers. Don't replace such support with a human helper. You won't find a helper who can keep your work as steady as a workbench.
When you cut with the bottom edge of the chain bar, the saw pulls away from you. That's good. But when you cut with the top edge, the saw wants to come at you. The most hazardous cutting spot of all is the top curve of the bar's nose. Using that point almost guarantees a kickback.Hold the chainsaw with both hands, and wear safety glasses or goggles. A full face shield is even better.