Tool Tales: The Pump Drill

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A pump drill is an ancient tool traditionally used to generate friction heat for starting fires, as well as for boring holes. The principle of a pump drill’s operation is easy to grasp, but hard to explain. It’s similar to the button spinner or whirligig, in which rotational momentum is built and maintained by repeated twisting and untwisting of a cord.

Early pump drill

Primitive Technology Volume 1I first got interested in pump drills after reading a 1993 article by Anthony Follari, originally published in the Bulletin of Primitive Technology #6, about the design, construction, tuning, and operation of fieldcraft pump drills for fire-making and hole-boring. That article, and many other fascinating pieces from the Society of Primitive Technology, has been republished in an outstanding compilation called Primitive Technology: A Book of Earth Skills. After reading it, I got interested in the idea of a “modern” pump drill, operating on the same principle as the ancient tool but manufactured using industrial-age materials instead of wood, stone, and bone.

Pump drill, as illustrated on p.336 of Gardner Dexter Hiscox's 1903 Mechanical Movements, Powers and Devices.

Pump drill, as illustrated on p.336 of Gardner Dexter Hiscox’s 1903 Mechanical Movements, Powers and Devices.

Flat drills, ca. 1822, from Thomas Gill's Technical Repository.

Flat drills, ca. 1822, from Thomas Gill’s Technical Repository, plate VI.

A bit of research revealed that, in fact, small pump drills were manufactured and regularly used up until the early 20th century, at least, primarily by metalworkers—silversmiths, jewelers, and clock- and watch-makers—to bore small holes in homogeneous materials like brass, precious metals, and stone. The reciprocating action of a pump drill is most efficient when the bit can cut on both clockwise and counterclockwise strokes, and modern “twist” drill bits are designed to cut in one direction only. Therefore jewelers’ pump drills were commonly fit with simple flat drills as illustrated above and to right. A bud bur or other achiral grinding tool would’ve been another option.

19th century pump drill

I knew from reading around the web (e.g. on Treewright’s blog) that a few of these 100-year old tools were still floating around the antiques market, so I set up an eBay auto-search for “pump drill” to see what surfaced. That was late 2009, as I recall. It took awhile, but, sure enough, about three months back that search turned up the specimen shown above, which I snagged for just under $40 including shipping. It’s 12-1/4″ long, from the end of the shaft to the nose of the collet, and 9-3/8″ wide across the handle. The flywheel is brass, 2″ in diameter, and the whole tool weighs a bit under half a pound (210g).

Handle tie detail

When it arrived, the pump drill was fit with a piece of flat braided cord that, I suspect, had been part of an old shoelace. The possibility that this was the original cordage seemed remote, at best, so I didn’t hesitate very long before cutting it off and, following the example of Practical Machinist forum member gwilson, replacing it with a piece of 1/8″ leather cord about 20″ long.

Chuck detail

As received, the collet jaws did not tighten noticeably, even when the cap was tightened down as far as it would go. I solved this problem by dismantling the chuck and shimming the collet forward, just a bit, with a small piece of plastic cut from an old plastic swipe card. I just dropped this into the bottom of the receiving sleeve and reassembled the chuck. Thus modified, it accepts round stock between about 1/16″ and 1/8″ in diameter.

One of the advantages of using a pump drill over a bow drill, brace, or other manual boring tool is that a skilled user can operate a small pump drill with one hand, while using the other to position and steady the work. In the embedded video, YouTube user zeiglerr demonstrates that trick. Though the tool he’s using is an antique, like mine, he points out that Swiss watchmaker supply firm Bergeon & Cie offered a very similar model (#1312-30) in their catalog (PDF) as recently as 2002!

Bergeon & Cie 1312-30

Using my pump drill, it takes about 30 seconds to drill a 1/16″ hole in 1/16″ sheet brass, using a modern twist bit made of high speed steel. I start by marking the drilling location lightly with a center punch and applying a drop of mineral oil to lubricate the cut. I also lubricated the shaft of the drill, the first time I used it, by rubbing it a couple times across a bar of soap. Friction is the great enemy when operating a pump drill, because if the bit binds you lose all the momentum in the flywheel and you have to rewind the cord and pump it up to speed again.

I experimented with making my own flat drills by cutting off and filing the tips of small flat-blade screwdrivers, and was able to actually bore a couple holes with these. Twist drills of equivalent diameters, however, were always cleaner and faster, in my hands, even though they theoretically only cut on a 50% duty cycle. I haven’t tried it with a bur, yet, but I think that’s next on the list.

Arcade Controls on Raspberry Pi


Retro-arcade gaming is more than recreating the sound and graphics of bygone video games. To anyone who spent endless hours of their childhood feeding quarters into rows of pulsing, blaring machines, the feel of the industrial-grade joysticks and buttons is an essential part of the experience. Thankfully, Raspberry Pi can help recreate the feel of those games.

There are a number of ways to attach Happ joysticks and microswitch buttons to a Raspberry Pi, starting with directly connecting switches to GPIO pins, but because arcade emulation programs like MAME look for keyboard events, the simplest way to integrate industrial controls is with a keyboard encoder. These keyboard encoders connect in place of (or in front of) a standard keyboard and provide enough switch inputs for one or two joysticks and a number of input buttons. All recently made keyboard encoders will work with late-model computers (including the Raspberry Pi). The first generation of these encoders came out before there were USB keyboards, so they only emulate IBM PS/2 keyboards (which date back over 25 years). A local friend of mine, who is also into retro-gaming, recently upgraded his 1999 HanaHo HotRod arcade joystick platform to a newer USB-compatible platform and sold the old HotRod to me.

The full details of getting the HotRod to work with Raspberry Pi are on my makerblog.

Here’s a closer view of the Raspberry Pi and the Inland MA3303 adapter:


Roentgens’ Desks, 18th Century Transformers

If this video of a desk from 18th German cabinet makers the Roentgens (pronounced “RUNT-ghen”) doesn’t blow your neck bolts, nothing will. This and other furniture from the father and son team of Abraham and David are part of “Extravagant Inventions: The Princely Furniture of the Roentgens,” at the Metropolitan Museum of Art until Jan 27th. [Thanks to Alberto Gáitan and Stephen Ellcock!]

The Poor Man’s James Bond

A friend here at O’Reilly swung by my office the other day and commented on the copy of the Anarchist Cookbook I had on my desk and that I should check out The Poor Man’s James Bond. He had a picked up a copy of it a few years ago at a garage sale and brought it into work for me to check out.

According to Wikipedia, the book was compiled by former American Nazi Party member Kurt Saxon (credited with coining the term “survivalist”) and it was geared at the growing survivalist movement of the 1970s and 80s. It was a counterpoint to the Anarchist Cookbook, which he claimed contained many inaccuracies.

The second issue of The Poor Man’s James Bond talks about improvised weapons that could be made legally using common household items. It also had a number of easily made and readily available booby traps and a number of other explosives recipes. In addition, the book covered fireworks, chemistry, archery targets, scrap spearguns, and more!

We took a few pictures of the book and I got a kick out of all of the potentially very dangerous projects involved. It reminded me of the The Dangerous Book for Boys for grownups.

In the preface, Kurt recounts a time where he was making concussive caps and nearly lost an ear and his hearing when it was mixed improperly. So, remember to read the directions all the way through, get a Ph.D. in chemistry, and then start building.

[make_slideshow slug=”the-poor-mans-james-bond” link=”Launch the Slideshow” title=”The Poor Man’s James Bond”]

Lindsay’s Technical Books Ships Last Catalog

“No orders accepted after February 28.”

It’s the end of an era, folks.

I think I was fourteen or fifteen when I received my first Lindsay’s catalog, ordered from a print ad in the back pages of Popular Science or Popular Mechanics—I don’t recall which. “Build Lightning Bolt Generators!” it trumpeted. “Melt Metal! Rediscover Lost Technology!”

I clipped along the dotted line and sent $3.00, cash, through the US mail. I’ve been a regular buyer ever since.


Remarkably Wee Tool Chest

Photo: Bruce Dale

MAKE alum Rachel Hobson points us at this delightful 1/12 scale miniature replica of an antique tool chest from Colonial Williamsburg. The artist is William Robertson:

Robertson’s tool chest contains all the same tools that were found in the original. All the tools work, even the plane’s tote (handle) is set a scale 1/8″ to one side as the original. The saw has 160 teeth to the inch. Robinson says that the hardest tool to make was the folding rule with 5 leaf hinge. It is about .030″ thick and hand engraved on boxwood. Things like the shears and dividers also have nice little joints.

The tiny hand plane sharpening the pencil is an especially nice touch. Click through, below, for many more astounding details. Fine Woodworking has a narrated slideshow showing off more of Robertson’s work. [Thanks, Rachel!]

William Robertson Miniature Tool Chest » The Toolchest Site

More: Hamler Tools — Miniature Replica Tools

Snakes on a Game

“Enough is enough!  I have had it with these blankety-blank snakes on this blankety-blank, um…ARM…Cortex-M0, ah, microcontroller.”

Ahem, right.  Anyway.

Apologies are now due to hardworking Hack a Day writer Mike Szczys for reducing his latest tasty MCU project to a perfunctory SamJack joke.

In point of fact, the name of the game is just Snake, with no s at the end, and though it’s about as old as personal computing, itself, Snake really made its mark in 1998, when Nokia started bundling it as the default videogame on its then-new ARM-based cellphones.  Which is why it’s doubly cool that Mike is playing the game on a chopped-off screen from an old Nokia 3595:  He’s built a handheld Nokia Snake machine, circa 2002, without all those annoying phone functions that really just distracted from the game, anyway.

Circuit, source code, and more details are available at Mike’s personal site, linked below.  [Thanks, Mike!]

Snake game on an ARM microcontroller | Jumptuck

Maker Faire New York: Patent Model Museum Visit

A few weeks ago, I had the pleasure of visiting the Rothschild Petersen Patent Model Museum in Cazenovia, NY (my flickr set is here).

The museum is run by Alan Rothschild, who is the author of an upcoming book from MAKE on some of the amazing patent models in the museum collection as well as the history of patent models.

But that book won’t be coming until next year. The good news is that if you need a taste of these models, you can check out Alan’s exhibit at our third annual World Maker Faire New York (September 29 and 30 at the New York Hall of Science). And if you can’t get enough patent models, you’ve got until November 2013 to check out the 32 models from the museum that are on exhibit at the Smithsonian American Art Museum: Inventing a Better Mousetrap: Patent Models from the Rothschild Collection.