27 Facts About Drill bit

Nowadays, the drill bit is usually made by rotating the bar while moving it past a grinding wheel to cut the flutes in the same manner as cutting helical gears.

Such a Drill bit is generally self-starting and can cut very quickly.

Step drill bit is a drill bit that has the tip ground down to a different diameter.

The short length of the uniDrill bit and ability to vary the diameter of the finished hole is an advantage in chassis or front panel work.

In either use, the name seems appropriate, as the Drill bit is either establishing the center of a hole or making a conical hole for a lathe center.

However, the true purpose of a center drill bit is the latter task, while the former task is best done with a spotting drill bit .

When drilling with a hand-held drill the flexibility of the bit is not the primary source of inaccuracy—it is the user's hands.

An ejector drill bit uses a specially designed carbide cutter at the point.

The bit is hardened and coated against wear far more than the average drill bit, as the shank is non-consumable.

Spade drill bit for metal is a two part bit with a tool holder and an insertable tip, called an insert.

Brad point drill bit is a variation of the twist drill bit which is optimized for drilling in wood.

The brad point drill bit has the outside corner of the cutting edges leading, so that it cuts the periphery of the hole before the inner parts of the cutting edges plane off the base of the hole.

In metal, the brad point drill bit is confined to drilling only the thinnest and softest sheet metals, ideally with a drill press.

When reaming a pre-bored straight-sided hole, the spoon Drill bit is inserted into the hole and rotated in a clockwise direction with a carpenters' brace until the desired taper is achieved.

Originally the Forstner bit was very successful with gunsmiths because of its ability to drill an exceedingly smooth-sided hole.

Center bit is optimized for drilling in wood with a hand brace.

Edge of the bit has a sharpened spur to cut the fibers of the wood, as in the brad point drill bit.

Two styles of auger Drill bit are commonly used in hand braces: the Jennings or Jennings-pattern Drill bit has a self-feeding screw tip, two spurs and two radial cutting edges.

The Drill bit is the same style as that used in the gimlet, a self-contained tool for boring small holes in wood by hand.

The gimlet bit is intended to be used in a hand brace for drilling into wood.

Hinge sinker bit is an example of a custom drill bit design for a specific application.

Forstner Drill bit could bore the mounting hole for the hinge, but particle board and MDF are very abrasive materials, and steel cutting edges soon wear.

Diamond masonry mortar bit is a hybrid drill bit, designed to work as a combination router and drill bit.

Masonry bit shown here is a variation of the twist drill bit.

The key distinguishing feature of an installer bit is a transverse hole drilled through the web of the bit near the tip.

Once the Drill bit has penetrated a wall, a wire can be threaded through the hole and the Drill bit pulled back out, pulling the wire with it.

Once a hole has been drilled, the wire can be threaded through the shank end, the bit released from the chuck, and all pulled forward through the drilled hole.