Tag Archives: electrical

Finished boards

My Visit to RC4 Wireless

A few weeks ago, I visited Jim Smith out at RC4 Wireless. I was working on a magazine article about Cirque du Soleil’s new show, Kurios, and their use of RC4 Wireless units. Since Jim was just an hour down the road from me, I thought I’d swing by and see how they’re made.

If you’ve never seen or used an RC4 Wireless dimmer, think of a small box that lets you control electrical devices from your theater’s lightboard. So, if you wanted a flashlight, or a lantern to turn on and off during a light cue, rather then having the actor use the switch on the prop itself, these are one of the wireless dimmers that can make that happen.

Printed circuit boards
Printed circuit boards

When I got to his workshop and he showed me around, what surprised me most was the fact that he was building every single unit right there by himself. He starts with a printed circuit board, or PCB. These he gets made up at a factory, but then he prints the circuit paths on in his shop.

Pick-and-place machine
Pick-and-place machine

Next up, the boards go into his pick-and-place machine. Various components come on reels of “tape”. These are fed into the machine, which grabs what it needs, and places it exactly where it needs to go on the circuit board.

Before he got the pick-and-place machine, he was placing every component onto the board and soldering them in place by hand. Not only does the pick-and-place machine allow him to work much faster, but it allows him to use much smaller components. At a certain size, he has to use tweezers just to handle the components and a magnifying glass to see where to solder. He cannot physically work with anything smaller. With the machine, he can use smaller components, which mean smaller RC4 units overall.

Baking and testing
Baking and testing

Once all the surface mounted components are in place, he brings them over to an oven, which bakes the solder and locks everything in place.

Finished boards
Finished boards

He then adds the through-mount components. These are things like the DMX connectors or switches or anything that will be poked and prodded by a user. Using through-mounts gives them a strong mechanical connection. It’s basically like bolting the pieces on, where the pick-and-place machine can be thought of as “gluing” the pieces on.

CNC milling machine
CNC milling machine

The cases he uses are standard cases that he can buy in bulk. He then puts them in his CNC milling machine to cut out all the holes for connectors, switches and mounting hardware. The finished units then head inside his house where they get tested, programmed, labelled and packed. From there, they head off to companies like Cirque, where they are used for… well, you’ll have to wait for my magazine article to come out to see what they are used for.

Mid-Week Links

Things have been hectic here in the Hart Household, and you may have noticed I’ve missed a few posts. So I am switching things up and posting a bunch of links on a Wednesday rather than a Friday. Here we go:

Chris Ubick has been the props master on dozens of films, such as The HelpPractical MagicMilk, and The Internship. Dianne Reber Hart has written a great article on her life and career which you should check out.

This article is a few years old, but worth mentioning: The Last Electronics Project I Completed. It’s a little deep and heavy at times (the author was building a fake bomb prop in lower Manhattan in early September of 2001) but it brings up some questions about the questionable legality of what we sometimes find ourselves building.

On a lighter note, here is how to force a patina on carbon steel. Short answer? Shove it in a lemon.

And finally, here is an interesting Instructable on assembling a vacuum-formed model. If you have tried vacuum-forming before, you will know that making the parts on the machine is just the beginning. You still have to trim, assemble and reinforce the parts to get a usable prop. This Instructable steps through some of those processes to make a fake ammo drum.

Friday Prop Notes

These guys made a life-size pirate ship using nothing but cardboard and hot glue. And they did it all in five days.

I’m looking forward to the film Monuments Men, about a team of art preservationists who go behind enemy lines in World War II to rescue artworks stolen by the Nazis. Credits talks with the production designer, Jim Bissell, on how they created the locations of a ruined Europe for the film.

Here are some blank vintage labels you can download and fill in with whatever text or logos you need for your next period show.

If you ever wanted to get started with circuits and electronics in your props, but didn’t know where to start, Tested has put together a nice little guide to getting started.

And finally, here is a brief history of the coping saw, which I am sure will answer all the burning questions you have had about the coping saw.

20000 Objects in Opera Property Room, part 5, 1912

The following is the fifth portion of an article which first appeared in the New York Sun in 1912. You can catch up on the first partthe second partthird part and the fourth part.

In addition to the mass of less frequently used properties which are distributed among the storehouses there are at the opera house itself five large rooms filled with hundreds and hundreds of the objects oftenest in demand. In one of these rooms, which is called the armory, are rows of helmets, great stands of spears, racks full of guns, innumerable swords, including the famous one of Siegfried, the white one of Lohengrin and that of Telramund. Here is Caruso’s armor, which, as he dislikes to wear or carry anything heavy, is made of aluminum. His helmets are of aluminum too. These stage weapons are never sharp enough to do any damage, even if some one accidentally got in their way.

The guns are the real thing and are loaded with powder. A permit to keep explosives on the premises has to be had every time an opera is given in which guns are fired or conflagrations imitated.

In one of the property rooms at the opera house, which is always spoken of as “Frank Furst’s room,” an employee is generally at work rubbing up gun barrels, swords and armor, or polishing brass armlets. Guns are used not only on he stage, as in “Tosca” and “Carmen,” but off stage in taking up cues.

If a great crash is to be produced half a dozen stage hands are armed beside them with a prompt book following the score. As the cue approaches he counts, “one, two, three, four, five!” At five they fire simultaneously, while at the same time there comes a clap of stage thunder. The resulting noise is big enough for any kind of a crash.

A curious phase of the property department’s work is the way it sometimes has to dovetail a job with some other department. For instance, in the last act of “Tosca” there is a flag which floats on the top of the tower. It really does float, the breeze blowing it with every appearance of naturalness. An electric fan adjusted behind the side scenes provides the breeze. In this case the flag is put in place by the property department, while the electric fan belongs to the electrical department, which must see that it is set up and running.

In the second act of “Madama Butterfly” several large Japanese lanterns with standards are brought in by Suzuki and set about the stage. Lights are burning inside them. The third act opens with the same scene after a lapse of several hours, which passage of time is indicated by having the lights in the lanterns flicker and go out one by one. This is the way it is done. When the lanterns are brought on they contain lighted candles which come under the head of properties and which therefore are put in and lighted by some one in that department.

When the curtain goes down a property man takes out these candles. Then an electrician sees that the standards are placed over metal plates in the matting, Suzuki having set them in approximately the correct position. Then he puts in electric bulbs, wires from under the stage are connected with the metal plates, contact is secured through the base of the standard and the resulting light is then turned on and off from below to simulate a flickering candle flame. After the scene the electrician comes and gets his bulbs before the property man can carry off the lanterns.

This article will conclude in a later post. It was originally published in the New York Sun, February 25, 1912, page 16.

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

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.” 1

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”.   2

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. 3

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.” 4

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. 5

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.” 6 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.” 7

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.”  8

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”. 9 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.” 10

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.”  11

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.” 12

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.”  13 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.”  14

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.”  15

An advertisement from eight years prior claims, “The electric Lesto Portable Hand Saw Designed, Manufactured and Patented by Scintilla, Ltd., Switzerland, since 1944.” 16

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.

Notes:

  1. A Youthful Sixty-year-old: The Jigsaw Celebrates Its 60th Birthday. Bosch Media Service, 4 June 2007. Web. 23 Apr. 2012.
  2. Murray, James A. H., ed. A New Dictionary on Historical Principles. Vol. 5, Part 2. Oxford: Clarenden, 1901.
  3. Bachmann, Martin. Bautechnik Im Antiken Und Vorantiken Kleinasien: Internationale Konferenz 13.-16. Juni 2007 in Istanbul. Istanbul: Ege Yayinlari, 2009.
  4. The Saw in History. Philadelphia: H. Disston & Sons, 1916, pg 27.
  5. Diderot, Denis, and Pierre Mouchon. Encyclopédie; Ou Dictionnaire Raisonné Des Sciences, Des Arts Et Des Métiers, Vol. 2. Paris: Briasson etc., 1751.
  6. 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.
  7. Ibid. pg 965
  8. 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.
  9. Whipple, Carlyle. Method of Hanging and operating Reciprocating Saws. Patent 16416. 13 January 1857.
  10. Wendt, Carl E. “These Jig-Saw Puzzles.” Boys’ Life Mar. 1933: 16.
  11. “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.
  12. “Electricity as a Hobby.” The Sun (New York City) 20 Mar. 1881: 5. Library of Congress. Chronicling America: Historic Newspapers. Web. 3 May 2012.
  13. Pickering, Albert V. and Moore, Albert H. For a motor-operated jig-saw. Patent 1826188. 6 Oct 1931.
  14. Briggs, Martin. Power tool. Patent 2240755. 6 May 1941.
  15. Gallager, Sheldon M., and Ralph Treves. “Electric Handsaw: Year’s Most Exciting Power Tool.” Popular Science Mar. 1958: 168-73. Print.
  16. The Electric Lesto Portable Hand Saw. Advertisement. The Wood-Worker Aug. 1950: 65.