Tag Archives: pump drill

Tool of the Month – Pump Drill

Pump Drill

I was all set this month to write about what I was taught is called an Archimedes drill. While researching it online, I discovered that this tool is actually called a pump drill and an Archimedes drill is something different! So, no interesting information on Archimedes to be found here today. He was pretty amazing, though, worth researching if you can find the time.

Pump Drill

The pump drill is composed of a long drill shaft with a collet on one end, a handle with a hole through the centre, a weighted flywheel, and a length of cord. The flywheel is attached near the bottom of the shaft and the handle slides over the top. The cord is run through a hole near the top of the shaft and affixed to either end of the handle so that it hangs just above the flywheel. To use it, the correct size drill bit is inserted in the collet, one hand is placed on the handle while the other hand turns the shaft to wind the cord around its length, raising the handle near to the top of the shaft, where the cord becomes tight. Holding the drill upright and placing the drill tip against the material to be drilled, a smooth downward pressure is exerted on the handle causing the drill to rapidly spin. Once the bottom is reached, the weight is relieved and the drill allowed to rebound re-winding the cord around the shaft and the process is repeated. It is a simple concept but a skill that takes practice to master.

Ruby Ring - Raw Ruby and Sterling Silver Cocktail Ring

The pump drill is a variation of the bow drill, which has been in use for at least seven thousand years. As well as drilling holes, the bow drill can be used to start a fire using friction. My occasionally burnt fingers can attest to the heat that can be generated by a drill spinning – silver is a great conductor of heat, and I have not only heated my fingers but made burn marks in my bench peg by drilling a piece of silver before now! As well as my pump drill, I sometimes use my flex-drive with a drill bit attached for drilling holes – there is something far more satisfying about using the lovely, simple, ancient pump drill though!