Also known as a hole cutter, a hole saw is a kind of diamond cutting blade that has a ring or annular shape. It is designed in a way that it creates a hole in the material being cut without having to cut its core. As such, it is commonly used in a drilling process and is the most preferred option to twist drills or spade drills for big holes, those that are larger than 1 inch. The depth of the cup-like shape of the hole saw is what determines the depth to which the saw can cut. Many hole saws, even a diamond hole saw, have a short aspect ratio of diameter to depth. They are ideal in cutting thin workpieces but there are also longer aspect ratios which are available for certain applications.
Usually, a hole saw is consists of a metal cylinder that is mounted on an arbour. The cutting edge of the saw can either have industrial diamonds in it or saw teeth formed in it. The arbour carries the drill bit used to bore a centering hole and once the first few millimeters are being cut, the centering mechanism may not be needed anymore. But it can be kept throughout the entire cutting process as it helps to bore without the bit wandering in a deep hole. The common type of saw used to work on materials like metal, wood, plastic, and plaster has sawed teeth. But for boring holes in concrete, stone, brick, and glass, a diamond hole saw is the best option.
While under the main classification of diamond cutting blades, diamond hole saws are also known as diamond core drill bits. They can be used either in wet or dry drilling. Wet drilling is usually used on extremely hard materials such as reinforced concrete. This is because too much heat that is generated during the drilling operation can blunt the diamonds on the core bit, leading to the poor performance of the diamond core drill bits. In most cases, the bond materials used to weld diamond cutting blades can be made to suit both wet and dry drillings, making the core bits work better in drilling speed.