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The Add-em toy adding machine


The Add-em toy adding machine
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The Add-em toy adding machine

Add-em is a toy adding machine made by the Western Stamping Company under their Tom Thumb Products brand, and mine is probably from the late 1950s or early 1960s. The case is made of thin metal plate, connected together using tabs put through slots. It has a 3-digit register, and three buttons marked 100, 10 and 1. Pressing a button will increment the associated digit in the register, and also perform any carries. It does not have a clearing mechanism.


The instruction sheet on the bottom says:

INSTRUCTIONS Add-em adds from 1 to 999. For example if you want to register 222 push each key twice. To add 321 to 222, push No. 1 key once, push No. 2 key twice, push No. 3 key three times. This will total 543. To clear push keys to zero. TOM THUMB PRODUCTS WESTERN STAMPING CO. Jackson, Michigan, U. S. A.  

The mechanism is ingenious. Strictly speaking it does not have a carry mechanism, as it is not the rotation of a wheel that cause the next wheel to turn. Instead, each button directly drives their own wheel, and also any wheels that need to be turned to take care of carries.


The number wheels are plastic, and have a 10-toothed saw-tooth gear on one or both sides. The buttons operate a pawl that pulls such a gear one tooth. The 100 button and the 10 button both uses the gear on the left side of their number wheel, and similarly the 1 button uses the gear on the right side of the right wheel. The gear on the side of the tens number wheel has a deeper notch between the teeth at the digit 9, so that the pawl controlled by the 10 button drops deeper and also connects to the slightly smaller diameter saw-tooth gear on the right side of the hundreds wheel, so that the button action will turn both wheels.

A compound version of this is used for carries from the the units wheel. The 1 button is connected to a second pawl that lies between the units and tens number wheels. This pawl is purely to execute the carries, as the units wheel itself is rotated by a separate pawl on the right. The carries pawl is held away from the gear on the tens wheel by riding along a smooth ring on the left side of the units wheel, except that when that units wheel is on 9, there is a gap that allows the pawl to dip and engage with the tens wheel. The gear on that tens wheel has a deeper notch at the 9 digit, so that when the units wheel and tens wheel are both on 9 then the pawl dips even further an engages with a hidden metal gear that is attached to the axle. The hundreds wheel is also fixed to that axle so that it will be moved by the button press too.


Here is a video where I demonstrate the Add-em.

In this video I show the Add-em's mechanism.


tomthumblogo The Western Stamping Company was an American company based in Jackson, Michigan. It was founded in August 1939 at 1613 Wildwood Avenue by Arthur Poole, Kirby Baker, Floyd Hardick and Ed Snell. They made various items, including things for the war effort, but it wasn't until near the end of the war that they made their first toy. It was a toy cash register, designed by Lathrop Berry. It had several buttons, and each would ring a bell and pop up a sign with a different price in the display. Another button would make the cash drawer pop open which contained toy currency. This was a huge success, and they made half a million of them every year for many years. It was marketed under the Tom Thumb products brand name.

Around this time they started to make the Add-em, and apparently Floyd Hardick was the person responsible for it. Note that there exists a Tom Thumb Adding Machine, which was an addiator/troncet type of adder, with 9 digits and 8 sliders, but I have found nothing to indicate that this was in any way related to the Western Stamping Company.

The company needed to expand in about 1950 so it moved to 2203 West Michigan Ave. There it started to make many other metal toys, including from 1953 onwards a very successful fully functional toy typewriter. It had a 3-row keyboard, 28×2 characters, and used a standard width ink ribbon. Almost all the patents assigned to the company, including those for the typewriter, are by James E. Thomson who joined the company back in 1941.

unclesamslogo In 1957 Western Stamping took over the Durable Toy & Novelty Company. That company had been making Uncle Sam coin banks since 1907. These are coin banks that look like cash register, which count the coins inserted and only unlock once a certain total is reached. A version that recognised 3 types of coin was introduced in 1923 (patent filed in 1912, US 1,269,608, A.E. Jacobs). Western Stamping continued to make them, but made changes to make it cheaper to manufacture. Durable Toy also made a toy movie projector and a toy baby grand piano, but I don't think Western Stamping ever made those. In 1960 Western Stamping created and trademarked a new Tom Thumb logo, with a boy doing a thumbs-up sign in between the words Tom Thumb.

In the early 1960s James E. Thomson left to start his own toy company, namely Jet Design Co., still in Jackson, located at 3519 Wayland Drive. The vice president was Lewis N. Masters who also used to work for Western Stamping. In 1965 Arthur Poole sold the Western Stamping company to Jet Design, so from then on James E. Thomson was president of Western Stamping. Under his direction they continued to make toy cash registers, coin banks, and toy typewriters.

Over the years the American production plants became less competitive so by 1975 the last production plant in Jackson closed. All the production was done in England and Japan, and later other countries like South Korea. A few years later, the British company Byron International bought the majority share in the company, and its head offices in Jackson were closed. In 1982, Ohio Art was licensed to make and distribute some of the toys, including the Uncle Sam coin banks.

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The earliest advertisements for the Add-em are from late 1947, and for the first year or so it had a clearing mechanism in the form of a knob on the right hand side that you had to turn. There are not many later ads at all. The colour advertisement is from an eBay auction and did not include the publication date but as it uses the Tom Thumb logo it is probably early 1960s. Advertisements for Western Stamping's other products are fairly common after 1955.

1947-11-12 Detroit Free Press (Michigan)
1947-11-25 Battle Creek Enquirer (Michigan)
1947-12-18 Pittsburgh Sun Telegraph (Pennsylvania)
1948-11-25 The Peoples Banner (David City Nebraska)
1948-12-02 The Gazette (Cedar Rapids Iowa)
1948-12-10 Iowa City Press Citizen
1949-11-24 Iowa City Press Citizen (Iowa)
1956-10-18 Rolling Hills Herald
1956-12-07 Louisville Times
1957  McCulloch's Toy Guide
1965-12-16 San Bernardino Sun
1966-11-06 San Bernardino Sun
1972-11-23 Santa Cruz Sentinel
1976-06-22 Federal Register
1985 Collecting toys for fun & profit - William C. Ketchum Jr


I would imagine that the ingenious mechanism of the Add-em is patented, but I have not been able to find anything. I have however found many patents for the other toys sold by Western Stamping and the company Durable Toys they bought.

PatentFiling datePriority dateNameDescription
US 1,269,60825-03-191218-06-1918Arhur E. JacobsThree-coin-register bank
US 1,906,36117-03-193202-05-1933Lathrop F. BerryToy cash register
US 2,262,47515-07-193711-11-1941Jacob D. StirissCoin register bank
US 2,392,42407-11-194108-01-1946Jacob D. StirissCoin register bank
US 2,431,35125-10-194425-11-1947Jacob D. StirissCoin register bank
US 2,458,85004-01-194711-01-1949Floyd W. Hardick / Ruth P. BerryTarget release actuator for toy cash registers
US 2,458,86310-01-194711-01-1949Henry A. Kroenlein / Ruth P. BerryCombination key holder and tension member for toy cash registers
US 2,705,55301-05-195105-04-1955James E. Thomson / Western Stamping Co.Typewriter construction
See also: GB 759,519.
US 3,045,90225-01-196024-07-1961James E. Thomson / Western Stamping Co.Toy cash register
US 3,048,94014-11-196114-08-1962James E. Thomson / Western Stamping Co.Toy bank vault construction
US 3,057,44921-03-196009-10-1962James E. Thomson / Western Stamping Co.Typewriter
See also: CA 698,149.
US 3,239,05020-10-196408-03-1966James E. Thomson / Western Stamping Co.Ribbon drive for typewriter construction
US 3,387,61610-04-196711-06-1968Harold E. Bortz / Western Stamping Co.Coin sorting and despensing device
See also: CA 839,488.
US 3,957,19828-08-197418-05-1976James E. Thomson / Western Stamping Co.Toy cash register
See also: CA 1,047,766, GB 1,488,203, GB 1,488,204, US 4,093,848.
US 3,978,96121-04-197507-09-1976James E. Thomson / Western Stamping Co.Typewriter carriage actuating mechanism
US 4,000,80221-04-197504-01-1977James E. Thomson / Western Stamping Co.Type bar actuating mechanism
US 4,025,75626-04-197624-05-1977James E. Thomson / Western Stamping Co.Toy cash register
See also: CA 1,064,701, CA 1,064,702, CA 1,075,902, CA 1,106,605, GB 1,532,765, GB 1,532,766.
US 4,079,68415-11-197621-03-1978James E. Thomson / Western Stamping Co.Sewing machine
See also: CA 1,044,526, GB 1,481,366, GB 1,481,367, GB 1,481,368, GB 1,481,369, GB 1,530,875, US 4,111,141.
US 4,311,90111-12-197919-01-1982Mikio Ogawa / Western Stamping Co.Cash register mechanism
See also: GB 2,064,343,


Rechnerlexikon has brief pages for the Add-em, Tom Thumb Adding Machine, and Tom Thumb Products.
Rechenwerkzeug has a page with various wheel adders including the Add-em, and photo of its internals.
Michigan Live has a great article with lots of information about Western Stamping: Peek Through Time: Toys from Western Stamping Co. filled Santa's sleigh for many years
Our Lovely World blog has a nice post about the Tom Thumb addiator.
typewriters.ch has a typewriter collection that includes the Tom Thumb typewriter.

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