Drills and Bits in the Middle Ages

by Jamie Hall on November 1, 2010

Note: This is an old post, that had to be re-posted during the transfer to Primitivemethod.org.

Before I get into the subject of drills, let’s briefly look at the nature of hole-making; that’s what drills are for, but they aren’t the only way to do it. Depending on the substance, it is possible to make holes by cutting or deforming. Chisels and drills belong to the first category, while punches and reamers stretch the metal (see below for a discussion of what I mean by reamer). In the modern day, we make most round holes with a drill, but with primitive technology, it might be easier to combine several methods. For example, a punch might be used to make the initial hole, which is then expanded with an awl, and then the final work done with a reamer, to make sure the hole is round and smooth.

Punches and chisels are covered in detail elsewhere, so let’s start with awls, gimlets, augers and reamers (a woodworking gimlet is pictured right). At their simplest, these are like drill bits, but handheld, or gripped in a simple handpiece. Nowadays, we’re accustomed to precision-machined tools, but these primitive tools might simply be tiny knife-shaped blade with two cutting edges. As time went by, and the equipment developed, a twist was added to this blade shape, eventually resulting in the twist drill as we know it. In particular, the gimlet is an example of this progression – it’s a more advanced form of the awl. The auger is a larger form of the gimlet or awl, and too big for my purposes; it was commonly used for joinery, although it had application in some masonry and large lapidary work.

The reamers at work are nothing like those used by most craftsmen – whether that is because they are specific to jewellery is unclear; it might just be that ours are very old. If you have a glance at the wikipedia page for reamers, the tool looks a little like a drill bit, with several cutting edges which remove material. The ones we use are different – they are long and tapered, have a pentagonal cross-section, and no cutting edges. Despite this they are extremely effective at enlarging holes, or even short lengths of tube. As stated above, they use deformation, not cutting. It might be that they are a distinct type of tool with their own name, but I’ve always been taught that they are reamers.

All of the above can be used alone, but they really come into their own when a drill is used. With one hand, the amount of torque that can be applied is quite small, and the at such a low speed, the risk of the bit catching and breaking would be quite high. There are several methods for increasing the torque and/or the speed of the bit; the oldest of these seems to be the bow-drill. I’ve had a hard time finding dates for the origins of this technology, but a look at Theophilus suggests that the bow-drill was feasible, and probably it’s more evolved form, the pump drill. While the bow-drill depends on the regular back-and-forth motion of a leather strip in addition to the downwards force of the users hand, the pump drill translates this into a simple up-and-down movement driven by a stone or lead flywheel. In Book I, chapter 28, and in III-36, Theophilus describes devices for milling gold for gilding and painting. Both have a flywheel, and while the latter is hand turned, the former uses a leather strip to supply half the turning energy, while the flywheel supplies the rest. What’s important here is not the precise function of each device, but the general principles that can be applied to other rotary tools. The hand pump pictured (above left) is from the Haandkraft blog.

Somewhere in the basement at work is a pump-drill, which I’m told I can have, if I can find it. Failing that, I’ll make one, as they are very simple. Even if the provenance is uncertain for them, it’s not an unreasonable stretch to use this over the bow drill.

For the drill bits themselves, I expect to find a wide range of materials useful, but how critical will the tool be? It might be that a punch, reamer and gimlet are all I need for the kind of work I’ll be doing – the twist drill wasn’t invented until the 1800’s, so I won’t be using any of those.


HalfTime October 3, 2011 at 15:11

Intriguing post. Thanks for providing photos of the types of drills that were used during this point of history. Were there any drills that you can crank by hand back then?

Jamie Hall October 4, 2011 at 11:20

There weren’t any gear-driven drills, like the hand-powered drills you see in a modern workshop, if that’s what you mean. But there were a wide range of different types in use throughout history. The pump drill is particularly efficient for small work, because it can be used one-handed. For larger work in wood, they were probably using augers with arms at the top that one or two people could turn. A great deal of work would probably have avoided drilling, and used punches instead. For wood working, I wonder if they ever burnt holes with a hot spike, and then reamed out the hole to the precise size that they wanted.

Donald Whitney February 18, 2012 at 13:11

The bow-drill was used in India long before it ever got to medieval Europe (although beads were drilled in Greece and Rome somehow in antiquity- possibly also with a bow drill). For drilling holes in rock they held a piece of harder rock in the drill tip (sometimes diamond).
For wood, the spoon-drill was common, although augers were also used (as depicted in the hausbooks).

Powered gear-driven items had to wait for water power – See 13th century Germany at Idarr-Oberstein for the enormous water-powered sandstone wheels for cutting cabochons, and there is a hole in the center of a 15 ton sandstone wheel that may not have been put there with a chisel. There are also records of “polishing houses” where items were sent to be polished (like suits of armor), which were water-powered based on their locations along the river, but I have not seen an exent example of one that survived – flooding rivers washed away all but the foundations.

Jamie Hall February 18, 2012 at 17:00

Thanks for your comments. I’ll have a look for info about the late medieval stuff – do you have any more on the records about polishing houses – sounds fascinating. I’ve discussed the issue of polishing with various other artisans and craftspeople, and the level of polishing in the pre-modern period is a controversial area, and one that interests me.

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