Rotary Hammer

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A Brief History of the Hand Drill

Perhaps the most significant difference between human beings and the rest of the animal world is our ability to create and use tools. Tools have enabled us to perform tasks that would be difficult or impossible to perform otherwise. The drill is a perfect example of this. Without a drilling device we would be hard-pressed making a hole in a material like wood, let alone harder materials like concrete or steel, not that concrete and steel would probably exist without the use of other tools anyway, but that is a tangent I will ignore.

If we follow the history of the drill back in time we come to the ancient Egyptians and Harappans, who used a device called a bow drill, which although more commonly used for making fire, was also used in rudimentary woodworking tasks. It was also used by the ancients’ equivalent of the modern dentist, the thought of which I am sure would increase the heart rate of anyone with a phobia about dental treatment. The components of this device are the bearing block, the spindle, the fireboard and the bow. The string of the bow is wrapped around the spindle, which is held in place at one end by the bearing block and at the drilling end by the fireboard. Leverage is afforded the user of this device by the string attached to the bow.

Another simple device which has been used for hundreds of years is the pump drill. The components of this device are the drill shaft, a heavy flywheel, a narrow piece of board with a hole in the middle, and some cord. The flywheel is joined to the bottom of the shaft and the piece of board is placed over the top of the shaft by means of the hole. The length of cord is placed through a hole in the top of the shaft and is attached to either end of the board. There is a hole at the end of the shaft in which the bits are placed. The board is then held in place while the shaft is rotated until the board has lifted to near the top of the shaft and the cord is tightly wound round the shaft. The tip of the shaft is placed on the material which is to be drilled and downward pressure is placed on the board. The shaft spins rapidly and when the board reaches the bottom of the shaft it is allowed to rebound causing the cord to once again wind around the shaft, and the drilling can re-commence.

A more familiar device is the brace and bit, which is a drill with a u-shaped grip. The user puts pressure on the top of the drill with one hand and is able to provide rotational movement via the u-shaped grip with the other hand. The u-shaped grip could be considered to be a kind of crankshaft that provides increased torque in comparison to other hand drills, but with a slower speed of rotation. Another tool from the not too distant past is the old hand drill which looks like an eggbeater, and has a handle to hold with one hand on one side, and a rotational device with a handle on the other side, which provides the drilling momentum.

Tradesmen from the past would wonder at the comparative ease with which drilling tasks are completed with modern electric drills when compared to their primitive counterparts.

There are many kinds of drills being used these days, most of which have a pistol grip, and there are variations on the standard electric drill, such as the hammer drill, which has a hammering action which enables it to drill into masonry. The hammering action is able to be disengaged when not required. A more heavy duty drill is the rotary hammer drill which combines the hammering mechanism with the rotational mechanism.

Cordless drills have provided a degree of independence from the requirement of being within cord’s length of an electric power outlet. While these drills have in the past suffered from the disadvantage of being reliant upon batteries which required regular charging and had a relatively short life span, in more recent times vastly improved battery technology is making the cordless drill a much more versatile option.

Perhaps in another hundred years or so drilling technology will have advanced to a point that will make our present technology seem as primitive to future generations as the bow drill does to us.

About the Author

Adrian is an online writer and researcher, and he invites you to visit his website 24v Cordless Drill for information about a range of tools, including the Makita 24v Cordless Drill.

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Can I drill a hole in a stone with an SDS rotary hammer drill?

I want to drill a hole, maybe 3/4" or less and two or two and a half inches long, into a loose stone, probably under four inches thick and one foot in diameter. I am told than an SDS rotary hammer drill with a Carbide Tip is the way to drill a hole into rock, but I have no idea how this device works and with a name like "rotary hammer" it makes me wonder whether I could safely and effectively use it on a small stone in a vise (as opposed to a mammoth, immobile rock). Does this device work like a jackhammer or is it primarily rotary motion?

1) A hammer drill is a regular drill that also has a pulsating action on the drill bit. Something like 60x per second it hammers as well as rotates. It's normally "the tool" for drilling into masonry, but I propose your small rock will be decimated by this action.

2) Use a good regular drill, corded, for torque, rather than a battery powered one. Clamp the heck out of the rock! Multiple clamps! If possible use a drill press, even an attachment if a real press is not available. Go slow and steady with a new masonry bit. Safety goggles, with side protection. Protect your groin and chest in case this thing breaks apart and throws schrapenel everywhere!

Do NOT wear gloves! It is normal practice to not wear gloves in drill-like operations as they can become caught in the drill bit and pull your hand into the bit causing much more damage than having not worn gloves. Read all the owners and instruction manuals for your project. My advice is not meant for the amateur.

For the record, drilling a hole in an organic rock just doesn't seem like a wise idea.

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