If we take an outside-beveled gouge and begin twisting it into a board, it will dig deeper and deeper, making a hole. Shell and spoon bits work just this way. Soup would run out the end of a shell bit, but spoon bits are turned up on the end just like their namesake. They cut on their rims and have to be scraped sharp on the inside with the ground-off corners of a triangular file. Chair makers greatly prefer them. They can begin a hole at right angles to a surface, then allow you to tilt the bit like a ball in a socket to continue boring at a new angle. They don't have a lead screw to split the wood, and can bore deeper before poking through the other side. An old spoon bit will often have marks filed across its back, depth guides for the chair maker who owned it before you. Tapered square tangs make these bits interchangeable, but many coopers and chair makers used spoon bits, each permanently set into an individual wooden brace.
A nose bit keeps the semi-cylindrical form but adds one upturned cutting lip. Unlike the larger, T-handled versions, these smaller bits will usually start themselves without you first having to gouge a centering pocket. You can sharpen the lip of a nose bit with a small file. Even more filing can reshape broken or very worn nose bits into shell bits, extending their boring lives.
Center bits have about as elegant a design as you will find. The central pike drills in and holds the outer spur in perfect circular orbit around it. The spur knifes down into the grain and defines the perimeter of the hole. The blade enters and, like a rotary chisel, sweeps out shavings of wood as the bit is forced deeper into the hole.
Center bits look too simple to perform as well as they do. They don't eject shavings in deep holes, but they cut perfectly clean and round. As with any bit, you can make a cleaner exit hole by clamping waste wood to the far face. More often, when the pike begins to poke through on the other side, you flip the piece over and bore back to meet the original hole. Take it easy, though. The
center bit can poke through before cutting that last part, leaving a web but not enough wood to keep the bit centered.
Spiral bits evolved from the center bit in the late 1700s but did not become common for decades. Walter Rose, in his memoir of an 1880s English carpenter's shop, recalled that his father's tool chest had specially prepared places for center and shell bits, but none for the newly introduced spiral bits.
Auger bits are usually stamped with a number indicating their diameter in sixteenths of an inch. Bits are also made with lead screws giving different rates of progress for fast or fine work. The lead screw on any give spiral bit draws the cutters into the wood at a constant rate, so you can keep track of the depth of a hole by counting the turns as you progress. The lead screw also acts as a wedge, so it's wise to clamp the sides of narrow pieces.
Center bits and spiral bits benefit from the safe, untoothed edges of the auger bit file. The downward cutting nib or nibs should be filed only on the inside. The cutting lip only needs flattening on its gently angled bottom face—unless the nibs are getting too short. Over time, the nibs wear down, and if you don't file back the lower faces of the cutting lips, the nibs can become too short to shear.
Every bit drawer has its dogs and cats. The exotic Gedge pattern auger curls up its cutting lips like a waxed mustache. This breed digs in quickly, biting into end grain. Forstners have a century-long pedigree. Unlike other bits, Forstners track on their perimeter instead of their centers. They can dig flat-bottom holes partially overhanging a shoulder or deeply overlapping other holes. They're generally shallow-cutters and not fitted with a square shank for a brace. These factors, plus their greater cost, make them occasional rather than everyday tools — just like the homely expansive bit that can almost cut any size hole. As they say down at the Possum Lodge, "If a tool can't be handsome, it'd better be handy."
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There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.