Tungsten Carbide is the material which concrete bits are tipped with, without this tip, drilling into masonry would be all but impossible. The drill bit, which is held in a power drill, has two diameters, the diameter of the tungsten carbide tip, which is the diameter of the eventual hole and the drill bit shaft which is somewhat smaller in diameter. The shaft is not only smaller in diameter; it has rather deep flutes, both the diameter and the flutes are what allows the hole to be cleared of concrete dust and chips as the hole is being drilled.
Concrete bits are used for any type of masonry which can be brick, stone, concrete blocks or the mortar which holds them all together. When it is necessary to attach anything to walls of this nature, a hole must be drilled which will accept an insert which is then used to accept the fastener.
On the job site one can see two tools, one a simple hand drill that has a hammer function, and the other a rotary drill. Although the end result is the same, a hole in the concrete, the drill bits are different and they are not interchangeable between tools. Concrete bits that will fit in a hammer drill will not work in a rotary drill and vice-versa.
Tungsten carbide bits will not work for drilling a hole in wood or metal, for these materials different bits must be used. When drilling concrete, a variable speed drill is required so that differing power can be applied. At times the drill may be going through a sand mix and then hit a stone, without the ability to vary the speed and subsequent torque of the drill, getting through these different materials would be difficult.
The tips on concrete drills are a mixture of tungsten and carbide, this material is very abrasive. Depending on the material that is being drilled into, the bit can be very different. The more common bit is referred to as a “deep fluted” bit and it is the choice when drilling into concrete. The flutes allow for the easy disposal of the concrete cuttings as the hole deepens. Bricks and hollow blocks are usually drilled with a bit called a “fast spiral” tool.
To achieve the best results, make sure the bit is not worn, if it is the hole may be larger than intended and the anchor will not fit snuggly. Fit the bit deep in the chuck so that it can bottom out and make sure the chuck is tight. As you drill, it is recommended that you stop periodically, withdraw the bit and clean it of concrete debris; this keeps the drill from getting too hot.
