Wood drill bits are used when drilling holes in wood. These carbon steel, twist-type drill bits are not suited for drilling steel and will dull very quickly if used on any type of steel; they also break more easily than the high-speed steel drill bits. Wood drill bits come in many styles to accommodate different jobs. For example, a spur point bit is used when smooth, straight holes are needed and bullet point bits are used for wood that could easily splinter. There also are flat bits and auger bits used for various wood drilling jobs.
The spur point drill bit is used when drilling holes for use with wooden dowel pins. These wood drill bits have a pointed center, coupled with two spurs on each side of the drill bit. This design bores extremely straight holes with smooth sides. Often referred to as a dowel bit, this style of wood drill bit should only be used on wood or soft plastic.
The bullet point, twist-type wood drill bits are often used when creating a clean hole is required. The pointy nose on this drill bit cuts smoothly through the wood and does not splinter around the hole as the bit breaks through. The bullet-style point on the end of the drill bit makes it easier to position it in the exact spot than other twist-type drill bits.
Flat style wood drill bits are often used to bore large holes in wood. Equipped with a sharp point in the center of two flat sides, this style of drill bit leaves a very flat bottom at the end of a bore. The downside to this style of drill bit is that the wood often splinters as the drill bit exits the wood, leaving a very rough finish to the hole. These drill bits also require a very powerful drill motor when boring very deep or when using a large bit.
When using a hand-operated brace to bore deep holes, wood auger drill bits are the best choice in most cases. These wood drill bits use a screw-like center point to actually aid in pulling the bit into the wood. A single spur positioned on the edge of the bit helps to cut straight through the wood. These wood drill bits also produce a flat bottom in the hole and are well-suited for installing dowels in a handrailing or fence. It is important to keep the cutting edge of this type of drill bit sharp so it is easily turned by hand.