Tag Archives: tool

Links for the Weekend

Here’s a story about a prop master who has found a new career killing zombies. I think most props people imagine they would be pretty well equipped to fight zombies.

Adam Savage (of Mythbusters fame) has quite an intense and detailed tutorial on making a silicone rubber mold with a plaster mother mold (or as he calls it, a “hard shell mold”). It is perhaps a bit more involved than most theatrical prop shops would ever need, but a lot of the extra steps he does are to keep the mold from collapsing on itself and to ensure the two halves are lined up perfectly.

What do you want to know about drill bits? How about everything! Ok, so this free PDF guide to drill bits deals only with woodworking (no metal or plastics), but it is still a useful amount of information available at a glance.

This is kind of cool. A classmate of mine from undergrad wrote a play a few years ago called The Love of Three Oranges. One of the productions of this play is documenting the construction of their set and props on a blog.

So, I’ve talked about the invention of the jig saw before; its history is at least somewhat intertwined with the history of fret and scroll saws. Well, Chris Schwartz has a piece on the history of the coping saw, another tool sharing this history. I personally love my coping saw, and consider it one of the indispensable tools in my prop-making bag.

Who Invented the Jig Saw?

A few years ago, a press release came out declaring the history of that most useful of tools, the jig saw. It read:

“The jigsaw is celebrating its 60th birthday. About 60 years ago, Albert Kaufmann, who worked for the Swiss company Scintilla AG, invented the principle of the electric jigsaw. The inspiration for this came from his wife’s sewing machine: the very fast up and down action of the needle. By clamping a saw blade in this sewing machine, the inventor was able to produce extremely attractive curved cuts in wood. This represented the birth of a completely new tool. In 1947, Scintilla began series production of what was called the “Lesto jigsaw”, the first electric handheld jigsaw in the world.” [ref]A Youthful Sixty-year-old: The Jigsaw Celebrates Its 60th Birthday. Bosch Media Service, 4 June 2007. Web. 23 Apr. 2012.[/ref]

With the absence of any evidence to the contrary, this information has spread throughout the Internet, including to Wikipedia. For anyone researching the history of the jig saw, they will most likely find some quoting or paraphrasing of this press release; the fact that it is parroted on so many other web pages may make it appear that it is universally accepted as the truth.

While companies typically use press releases to extol the virtues of their own products and exclude all others, it is lazy for others to use such a press release as the sole citation in a history of the jig saw. The account given is an extremely simplified and unverifiable account of the history of such tools. We can see that better by examining the individual claims in the statement: that it is “the birth of a completely new tool”, that Kaufmann “invented the principle of the electric jigsaw”, and that the Lesto jigsaw was “the first electric handheld jigsaw in the world”. Along the way, we will get a much richer understanding of how many of the tools we use have evolved over time.

“The birth of a completely new tool.”

First, just what is a jig saw? The Oxford English dictionary defines it as “a vertically reciprocating saw driven by a crank, mounted in various different ways.” The term can be better understood by looking at the definition for jig: “To move up and down or to and fro with a rapid jerky motion”.  [ref]Murray, James A. H., ed. A New Dictionary on Historical Principles. Vol. 5, Part 2. Oxford: Clarenden, 1901.[/ref]

Hierapolis. Relief of an ancient double stone saw on the sarcophagus of M. Aur. Ammianos (2nd half of 3rd century AD).
Hierapolis. Relief of an ancient double stone saw on the sarcophagus of M. Aur. Ammianos (2nd half of 3rd century AD).

A reciprocating saw itself is nothing new; the Hierapolis sawmill from the second half of the 3rd century BCE used a reciprocating saw powered by a water wheel. [ref]Bachmann, Martin. Bautechnik Im Antiken Und Vorantiken Kleinasien: Internationale Konferenz 13.-16. Juni 2007 in Istanbul. Istanbul: Ege Yayinlari, 2009.[/ref]

A jig saw is used to cut curves, though. A 1916 book put out by famed saw makers H. Disston & Sons, Inc. explains the provenance of saws for cutting curves:

“As a matter of fact, Fret, Scroll and Jig saws are very similar, and are used for practically the same purpose… The Fret Saw is used almost always by hand… The Scroll Saw, the blades of which are somewhat wider, is used on heavier work, and although frequently worked by hand is also used in a machine run by foot or other power. The Jig Saw, though often confused with the Fret and Scroll Saws, is distinctly a machine saw, and is used on all heavy work…

The Jig Saw resembles Fret and Scroll Saws mainly in the purposes for which it is used. It is a sawing machine with a narrow, vertical, reciprocating saw blade, on which curved and irregular lines and patterns in open work are cut…

A species of Fret Saw is the Buhl Saw. The name of this saw is derived from André Buhl, an Italian. He was celebrated throughout France, in the reign of Louis XIV, for inlaid work in wood.” [ref]The Saw in History. Philadelphia: H. Disston & Sons, 1916, pg 27.[/ref]

The Buhl saw, characterized by its long, thin blade held on either end in tension, is the ancestor of the fret saw. The earliest illustration of one is in Diderot’s famed encyclopedia, first published in 1751. There, in Volume 2, on page 96, in the second plate for Boissellier (carver), is a small drawing. [ref]Diderot, Denis, and Pierre Mouchon. Encyclopédie; Ou Dictionnaire Raisonné Des Sciences, Des Arts Et Des Métiers, Vol. 2. Paris: Briasson etc., 1751.[/ref]

Buhl Saw, from Diderot's Encyclopédie, 1751
Buhl Saw, from Diderot’s Encyclopédie, 1751

Knight’s American Mechanical Dictionary provides some of the earliest descriptions and illustrations of jig and scroll saws. A jig-saw is “a vertically reciprocating saw, moved by vibrating lever or crank rod… Fig. 2723 is a form of portable jig-saw, which is readily attached to a carpenter’s bench or an ordinary table by means of a screw-clamp.”[ref]Knight, Edward Henry. Knight’s American Mechanical Dictionary. A Description of Tools, Instruments, Machines, Processes, and Engineering; History of Inventions; General Technological Vocabulary; and Digest of Mechanical Appliances in Science and the Arts. Vol. 2. Boston: Houghton, Mifflin and, 1884, pg 1215.[/ref] We can see figure 2723, the portable jig-saw, below:

Portable jig-saw, 1884
Portable jig-saw, 1884

The same book also has a definition for a tool known as a “gig-saw”. This machine is “a thin saw to which a rapid vertical reciprocation is imparted, and which is adapted for sawing scrolls, frets, etc.” [ref]Ibid. pg 965[/ref]

Gig-Saw, 1884
Gig-Saw, 1884

Lastly, the book defines a scroll saw: “A relatively thin and narrow-bladed reciprocating-saw, which passes through a hole in the work-table and saws a kerf in the work, which is moved about in any required direction on the table. The saw follows a scroll or other ornament, according to a pattern or traced figure upon the work.” [ref]Knight, Edward Henry. Knight’s American Mechanical Dictionary. A Description of Tools, Instruments, Machines, Processes, and Engineering; History of Inventions; General Technological Vocabulary; and Digest of Mechanical Appliances in Science and the Arts. Vol. 3. Boston: Houghton, Mifflin and, 1884, pg 2077.[/ref]

Scroll Saws, 1884
Scroll Saws, 1884

Interestingly, the dictionary also states, “the band-saw is a scroll-saw and operates continuously.” Indeed, under the definition for gig-saw, Knight writes, “Scroll-saws are usually gig-saws or band-saws.”

The earliest use of “jig saw” I’ve found is in an 1857 patent, which describes a reciprocating saw method that can be used “for small scroll or jig saws”. [ref]Whipple, Carlyle. Method of Hanging and operating Reciprocating Saws. Patent 16416. 13 January 1857.[/ref] The first occurrence of the term “scroll saw” I could find was in an advertisement in the March 1, 1843, issue of the New York Daily Tribune on the front page.

New York Daily Tribune, March 01, 1843
New York Daily Tribune, March 01, 1843.

“Invented the principle of the electric jigsaw”

So it seems strange to claim that Kaufmann’s discovery represented “the birth of a completely new tool,” since the jig saw predates the supposed 1947 discovery by nearly a century, and automatically reciprocating saws in general date back to around 250 BCE. But Kaufmann made his electric, right? That’s the real discovery, isn’t it?

Too bad we have this little nugget from 1933:

“The simplest sort of hand scroll-saws can be purchased for as little as fifty cents. Those of better quality cost a dollar or two. Old-style jig-saws, that are run by foot-power as the older sewing-machines are, can be had at varying prices, but average around twelve or fifteen dollars. You find fewer and fewer of these, however, as the modern jig-saws are nearly all electric.” [ref]Wendt, Carl E. “These Jig-Saw Puzzles.” Boys’ Life Mar. 1933: 16.[/ref]

Hand scroll saw and electric jig saw from Boys' Life, 1933
Hand scroll saw and electric jig saw from Boys’ Life, 1933

Not only does this article state that by 1933, electric jig-saws have become far more common than non-electric ones, but it also makes the interesting comparison between jig-saws and sewing machines, which is supposedly the flash of inspiration Albert Kaufmann will have in 14 years.

There were, in fact, a number of patents filed in the late 1920s through the mid 1930s for electrifying both scroll saws and stationary jig saws. Electrifying a jig or scroll saw was attempted as soon as possible at the advent of the Age of Electricity. An article in the 1888 Omaha Daily Bee states, “Besides, after using the batteries and motor during the summer vacation, you can unship them and take them home to run a sewing machine, a lathe or a jig-saw.” [ref]”Summer Excursions by Electricity.” The Omaha Daily Bee (Omaha, NE) 9 Jan. 1888: 7. Library of Congress. Chronicling America: Historic Newspapers. Web. 3 May 2012.[/ref]

Omaha daily bee, 1888
Omaha daily bee, 1888

Seven years before that, an article titled “Electricity as a Hobby” described a shop run in Brooklyn by Dr. St. Clair, a classmate of Thomas Edison. While listing the various novelties which have been electrified in his shop, it states, “The turn of a switch starts a self-feeding scroll saw by electricity.” [ref]”Electricity as a Hobby.” The Sun (New York City) 20 Mar. 1881: 5. Library of Congress. Chronicling America: Historic Newspapers. Web. 3 May 2012.[/ref]

So it would appear the “principle of the electric jigsaw”, claimed as an invention of Kaufmann, actually dates sixty years prior to the date claimed in the Bosch press release.

“The first electric handheld jigsaw in the world.”

But what about their biggest claim, that the 1947 production of the Lesto jig saw was the first electric handheld jigsaw in the world?

I found a patent issued in 1931 for “a motor-operated jig saw, adapted to cut wood, fiber, metal and other materials, with a simple and convenient operating means; to provide convenient means for manipulating the saw.” This jig saw features “a base having a flat supporting surface so that it can be moved at will over a flat surface.” [ref]Pickering, Albert V. and Moore, Albert H. For a motor-operated jig-saw. Patent 1826188. 6 Oct 1931.[/ref] The drawing below certainly resembles an electric handheld jig saw.

Pickering's 1930 jig saw
Pickering’s 1930 jig saw

Another patent, this one from 1941, describes providing “the benefits of jigsaw cutting, for example, to a portable tool.” [ref]Briggs, Martin. Power tool. Patent 2240755. 6 May 1941.[/ref]

Of course, patents do not necessarily mean that a working prototype was ever built. Even working inventions do not mean a commercial product was ever brought to market. Indeed, none of the above-mentioned tools seems to have been available for purchase. So while claims of being the “first” electric handheld jig saw in the world are debatable, the fact that the Lesto was the earliest model you can actually buy seems likely.

One of the earliest written histories of the electric handheld jig saw comes in 1958. The authors refer to the tools as “electric handsaws”:

“[Forsberg’s] Whiz-Saws were the first American-made electric handsaws. They appeared soon after the Swiss-made Scinta (now Lesto) was introduced into the U.S. in 1945… The electric handsaw has been around ever since the first Scinta saw (now called Lesto) was brought over in 1945 from the world-famous Scintilla Company in Switzerland. Scintilla had been attempting to develop a “portable jigsaw,” little dreaming it would become the husky, all-around workhorse it is today… Scintilla soon had a competitor. Forsberg, working in this country, brought out its now-famous Whiz-Saw, using a similar version of the still-expensive planetary-gear drive… Early sales went to a small and strangely assorted group of professional users, among them stagehands, builders, heating, plumbing and electrical installers.” [ref]Gallager, Sheldon M., and Ralph Treves. “Electric Handsaw: Year’s Most Exciting Power Tool.” Popular Science Mar. 1958: 168-73. Print.[/ref]

An advertisement from eight years prior claims, “The electric Lesto Portable Hand Saw Designed, Manufactured and Patented by Scintilla, Ltd., Switzerland, since 1944.” [ref]The Electric Lesto Portable Hand Saw. Advertisement. The Wood-Worker Aug. 1950: 65.[/ref]

So by 1950, it would appear the story is that Scintilla has been making the Lesto (previously called the Scinta) jig saw since 1944 and has been selling it in the US since 1945. This is pretty good proof that the Lesto was indeed the first electric handheld jig saw you could buy, though I am unsure why the 2007 Bosch press release claims the Lesto was first produced in 1947 rather than 1944.

So in conclusion, the history of the jig saw is a fascinating and complex history and is part of the general evolution of tools over the centuries. I do not mean to knock Bosch (I believe they still make some of the best jig saws in the world; it’s the brand I own), but for all the other websites presenting the “history” of the jig saw, I wish their research would delve deeper than a 97 word press release.

Blacksmithing

This past Saturday, I headed out to Efland, NC, where Dick Snow was teaching blacksmithing. It was another meeting with the Alamance Makers Guild (the same group that visited Roy Underhill’s shop last week). I’ve done various metalworking projects before, but never straight-up blacksmithing.

Dick tends the fire
Dick tends the fire

Dick had his coal forge fired up that morning. He also has a propane forge. He was telling us that while a propane forge does not need tending like a coal forge, a coal forge can get much hotter. You need that extra heat if you ever want to forge weld. We weren’t doing any of that, though; our lesson that day was making nails.

Cutting the rod on a hot-cut hardy
Cutting the rod on a hot-cut hardy

Dick teaches nail-making to new blacksmithers because it encompasses three of the basic techniques used in almost every blacksmithing project; drawing the steel out into a taper, cutting it to length and hammering it to give it a head. In the photograph above, you can see him cutting a red-hot rod on a hot-cut hardy. Sometimes called just the “hardy”, this tool is basically a wide cold chisel that sits in the anvil’s hardy hole. The tool sitting on the left of the anvil is the nail header. Because the nail is tapered, it only fits through that square hole to a certain point. You cut the rod a little above that point, then smash it down with the hammer into a mushroom-shaped head.

Dick teaches Ben proper hammer technique
Dick teaches Ben proper hammer technique

I would say the trickiest part of blacksmithing is all of it. I usually think of metal as the material you use for precision machining, and other materials are used for more organic and artistic construction. Blacksmithing, on the other hand, is where metal is used like a fluid, sculptural material. Even something as simple as making a nail is difficult to do consistently, at least at the beginning. I made about 6 or 8 nails, and none of them matched each other.

Refreshing the fire
Refreshing the fire

I’ve often thought it would be cool to use hand-forged nails in the furniture I build. You can find plenty of plans to make your own forges online, all the way down to a tiny brick-sized forge which can only make nails.

Hammering out a taper
Hammering out a taper

A case against Metric

Suppose you want to divide one foot into four parts: that is three inches. Divide a foot into three parts and you have four inches. Divide a meter into four parts: each part is 25 centimeters. Divide it into three parts and you are left with 33.33… cm.

The same is true with liquid and dry measurements. Take a cup. Now double it and you have a pint. Double it again and you have a quart. Take a gallon and divide in four; that’s a quart. Divide a liter into four parts, and you have to call it either 2.5 deciliters or 250 centiliters.

Look at a clock; it has sixty seconds in every minute, and sixty minutes in every hour. You can divide a minute in half, thirds, quarters, fifths, or sixths and in every case, you are left with a whole number of seconds. No fractions or decimals.

Metric may be good for scientific and technical measurements with things that increase by orders of magnitude. For example, hard drive memory started out with bytes, than kilobytes, followed by megabytes, gigabytes and now terabytes. But when dealing with carpentry and recipes and other measurements used in the construction of props, you are not having to convert between units which are one hundred or one thousand times larger than other units. You are dividing things into halves and quarters and thirds. You want to be able to take a measurement with a ruler which gives you one or two whole numbers and a fraction. It is so much easier to say “this prop is one foot and three inches tall, two feet and five inches long, and three quarters of an inch thick” than it is to say “this prop is 38.1 centimeters tall, 73.7 centimeters long, and 19 millimeters thick.” Furthermore, when you look at a tape measure, the hash marks for the fractions of an inch are all different sizes, so you can easily see whether you are at 1/4 or 5/16. With a metric tape measure, you have ten tiny divisions per centimeter, all at the same height. Is that .7 cm or .8? Who knows! (Of course, the greatest sin is a tape measure with both metric and customary units.)

The system of inches and feet were developed from commonly experienced physical objects, like a human thumb and a human foot. Their subdivisions were developed to measure commonly constructed objects for everyday use. This is what we deal with in props; the construction of everyday items on a human scale. A meter, on the other hand, was derived as a fraction of the Earth’s diameter. How much more sense does it make to say “this bench should be as long as three of my feet” than it is to say “this bench should be large enough so that 3,187,000 of them will fit end-to-end from one side of the planet to the other, going through the center”? Balderdash!

Metric is a centrally-designed hierarchical system which is applied to the measurement of everything conceivable, while customary units are a collection of localized systems specifically altered to the items and entities being measured. It may be funny to dig up archaic names of measurements to ask rhetorical questions like “how many hogsheads in a morgen”. In reality though, you will never need to convert the measurement of a cask of wine to the measurement for a plot of land. As an aside, archaic units are not limited to the customary system; does anyone in metric still use a stère?

It may be tricky to calculate how many inches are in a mile, but you rarely need to use that conversion in day-to-day life. Finally, despite the often touted ease of converting from nanograms to kilograms to megagrams, scientists have settled on essentially using the kilogram to measure the mass of everything, from the sun to an electron. No need to convert anything!

This is not so much a case against metric, but an appeal for hybrid systems and specificity in measurements to the task at hand. There is no harm done if I build a bench using inches and feet while biologists measure the volume of a cell in micrometers. I don’t wear the same outfit as a biologist, and a biologist doesn’t use the same tools and machines as a props artisan. That would be absurd. Neither of us have to convert the volume of a cell to the height of a chair. That would be even more absurd. Both of us using the same system of measurements? That’s the absurdest.

Tape measure

The Right Proper Links

These are so cool: US bread wrappers of the 40s and 50s. Besides being tons of fun, the pictures are good enough to print out if you need to make period wrapped bread. Incidentally, the site this is from, How to be a Retronaut, is chock-full of the most wonderful vintage and historical pictures. You can waste hours of time on this site while rationalizing that you are “doing research.”

I’ve pointed to the Early Office Museum site before, but I just found this gallery of Really Big Stuff. It’s photographs of early office equipment, like typewriters and rubber stamps, constructed at large scales (think “parade float” size). It’s also a good opportunity to check out the site if you haven’t heard of it before.

The NIOSH Pocket Guide to Chemical Hazards is an extremely useful source of information for the hundreds of chemicals listed as “hazardous” by OSHA and found in the stuff we build props out of. Rather than serve as an exhaustive guide to all information, it lists key information about each chemical relevant to work. You can view it online or download the whole thing as a PDF; I’m also throwing the link up in the sidebar of this site so you can find it every time you visit.

The Historic Naval Ships Association has a 1949 training manual titled Engine Room Tools presented in full on their website. It illustrates and describes the tools one would find on a ship at the time, namely metal-working hand tools. They are surprisingly similar to the metal-working tools you would find in a props shop, and the illustrations demonstrating their use are very cool.