How to drill concrete

Some of us may remember a time before the advent of power tools where we drilled holes in masonry and concrete. And not so long ago, for any large masonry project, a blacksmith was on hand to heat up and re-sharpen the chisels. (There were also special sharpeners for hand saws, but that's another story). To order the dismantling of concrete work, you need to go to the website.

And in this age of microchip tools, we're lucky we don't remember that, because the last thing before drilling into concrete with a power tool was quick or easy.

Previously, the best drill for concrete (and the only one) was a hardened steel drill, a sledgehammer and the strength of hands that Thor admired. Hit the chisel as if it were a nail, turn the chisel a quarter turn, repeat. Some bit tips had a star-shaped pattern, similar to what we would call an SDS bit today. Others were more like what we would call a “cold chisel.”

While the process remains the same—crush the concrete, remove dust from the hole—the tools have certainly changed.

The best drill bits for concrete

The best drill bit for concrete today is one of two tools: a hammer drill or a hammer drill. They both do essentially the same thing, but are completely different tools.

drill

You may have noticed that you can buy a cordless drill/driver or a drill/driver kit where the included drill has a hammer drill function. If you are going to purchase a cordless drill/driver, it is advisable to install the hammer drill function. Even if you don't need it right now, chances are you will need it.

The operating principle of a rotary hammer is to combine vibration with the rotational action of a conventional drill. The actual part that vibrates is called gubbins. Think of gubbins as two poker chips rubbing against each other at high speed. This creates enough vibration (and noise; these are loud and whiny tools) for the steel chisel to crush the hard material in front of it and for the flutes to remove most of it.

A hammer drill is designed primarily for random drilling and smaller holes—for example, plastic anchors and screws (say, for blinds or coaxial cable installation) or No. 10 screws for concrete.

What is the best drill bit for concrete?

While there is a lot of equality between general purpose bits, there are many factors that go into determining “best”, many of which are subjective and situation dependent. Perhaps the best answer to this question is that the “best” drill bit is the one you need to get the job done. (However, it can sometimes be difficult to tell the difference between bits.)

Generally speaking, impact drills look like regular twist drills with a carbide tip and a tighter knurl. Thanks to the smooth shank, they can only be used with a rotary hammer and a 3-jaw chuck.