#Drill bit size identification chart professional#

The largest gauge number (for example #107) indicates the smallest drill bit size and as the numbers decrease (#1), the drill bit size also increases.Īfter #1, the gauge number end and letters start with ‘A’ all the way up to ‘Z’. The Number & Letter Gauge drill bit sizes are very similar to American Wire Gauge (only in the representation but not the actual gauge numbers). In the U.S., Fractional Inch and Wire Gauge & Letter are very common whereas in the rest of the World, the metric drill bit sizes are predominant.ĭefined in the ANSI B94.11M-1979 Standards, the fractional inch drill bit sizes start from 1/64 inch and scale up all the way to 1inch with 1/64inch increments. Just like other gauges, the Drill Bit Sizes are also defined as per different international standards. But unlike spade bits, Forstner bit make flat bottoms. This bit also helps you make wider holes, just like spade bits. Forstner Bit: We use these bits primarily with drill presses rather than handheld drills.

The tip of these bits is wide and is usually made up of tungsten carbide, which is known for its strength.

Masonry Bit: As the name suggests, we use masonry bits to make holes on concrete, bricks, cement and stone.

Hence, we can consider a wood-spur bit as a cross between twist bit and a spade bit. Unlike conventional twist bits, which have a flat end, the Wood-Spur bit has a pointed end, just like a spade bit.

Wood-Spur Bit: Also known as Brad Point Bit, is a type of twist bit that is primarily used with wood.

The point end centers the bit for the hole and the paddle shape part will follow to make a wider diameter.

Spade Bit: This bit has a flat square shape with a point on the end to make wider holes particularly in wood.

Coming to sizes, twist bits are available from 1/16 inch to 1/2 inch. These bits come in almost all drill bits kits and you can use them to make holes in wood, metal, plastic, etc.

Twist Bit: This is perhaps the largest produced drill bit today.

Types of Drill Bitsīefore diving into Drill Sizes and Drill Bit Size Chart, let us quickly take a look at some of the popular types of drill bits. Depending on the type of material we are working on i.e., wood, metal, masonry etc., there are different type of drill bits. Speaking of chuck, it has two parts: metal jaws that hold shank of a drill bit and a plastic part that rotates to tighten or loosen the jaws.Īpart from these, a drill also has a forward/reverse switch, a torque collar to manually adjust the torque.Ĭoming to the Drill Bits, they are the main rotating parts that make the holes in wood (or other materials). A drill usually has a handle with good grip to hold the drill, a rechargeable and removable battery, a trigger switch and a chuck. The following image shows a typical cordless electric drill along with all its important parts.

#Drill bit size identification chart professional#

Cordless Electric Drills are becoming extremely popular in both the DIY community as well as with the professional usage. The main job of a drill is to make holes in wood, metal, masonry and other materials.

Drill Size Chart – Wire Gauge and LetterĪn electric drill is perhaps the most common and frequently used power tool.