Eimco Corporation Products

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Eimco Corporation (1935-1982)

- Eastern Iron and Metal Corporation (1918-1935)

- Eimco Corporation (1935-1982)

(The Eimco name was derived from "Eastern Iron and Metal Company," with Rosenblatt saying when he started his company, nobody would buy from any company with "Western" in its name, so he called his company "Eastern" which sounded more important. - Salt Lake Tribune, March 17, 1991)

(Eastern Iron & Metal Company formally changed its name to EIMCO in 1935.)

(Site 1 located at 634 South Fourth West)

(Site 2 located at 545 West Seventh South on north side of Seventh South, former Silver Brothers)

(Site 3 located on the southeast corner of Block 9, between 8th and 9th South, and 4th (500) West and 5th (600) West. Former Utah Junk, then American Foundry & Machine.)

January 26, 1935
"The EIMCO Corporation, formerly Eastern Iron & Metal Co., Manufacturers of Mining and Milling Machinery, 634 South Fourth West." (Salt Lake Tribune, January 26, 1935)

(The newspaper advertisements specifically for Eastern Iron & Metal ended in late December 1935.)

The 1935 reorganization of the Eastern Iron & Metal company was in response to the very successful Eimco Model 12B and 20 "Rocker Shovel," rail-mounted loaders operated by compressed air and used in narrow underground tunnels to scoop rock and dump it into waste-rock or "muck" cars. John S. Finlay was awarded U. S. Patent 1906001 on April 25, 1933, having applied for the patent on February 23, 1932.

Eimco-Finlay Loader

The Rocker Shovel Loader 12B provided a significant boost to underground mining productivity by automating the loading of waste rock, "muck" from underground mines, particularly in narrow mine tunnels. The loader replaced the use of manual labor and semi-automated loading of waste rock into mine cars. The Eimco rock loader was designed in 1931-1932 by Edwin Burt Royle and John Spence Finlay, employees of the Anaconda Mining Company's North Lilly mine in Eureka, Utah. The first working machine was called an "overshot loader" which described the loading from the front, passing the loaded bucket over the top of the loader itself and dumping the muck into a trailing mine car.

"Prior to 1931, their machine had a heavy bucket attached to a rail car by two movable rocker arms, and the car had air-motor powered wheels to push it into the rubble. In 1931, Joseph Rosenblatt of Eimco, Salt Lake City, met Royle and Findlay, and shortly thereafter, Royle joined Eimco as a consultant and designer. Where the first machine had been constructed from discarded Model T parts, Eimco developed it into the Model 12B that sold thousands." "Manufacturing rights were licensed to companies in Great Britain, India, South Africa and Japan. Sales expanded beyond the United States into Australia, Canada, Chile, France, Mexico, Spain, and Zambia. By 1969, 29,000 loaders had been sold." (American Society of Mechanical Engineers, Engineering Landmark #212)

(The first newspaper advertisement for the new Eimco-Finlay loader appeared in May 1932, offered by 'EIMCO,' Eastern Iron & Metal Co., Salt Lake City, Utah.)

(Read more about the Eimco Model 12B Loader at the American Society of Mechanical Engineers, Engineering Landmark #212)

The Eureka Reporter of October 15, 1931 a lengthy article about the Finlay-Royle loader, summarized below.

John S. Finlay, a local mining manager, has collaborated with mechanic Burt Royle to invent a new mechanical mucking machine, which they call the Finlay-Royle loader. The machine has been successfully tested for ten days at the Big Hill mine, where it has dramatically increased work efficiency. In one instance, it allowed the drift to advance 20 feet in a single day, and it can fill an ordinary ore car in just one minute and twenty seconds. At Big Hill, workers handled fifty cars in four hours—a feat considered remarkable—and up to 140 cars were moved across three shifts.

A key advantage of this new "mucker" is its compact size. Unlike most existing mucking machines, which require large headings of about 8x8 feet and cannot fit in standard mine drifts, the Finlay-Royle model operates effectively in a drift as small as 4x7 feet. It runs on air power from a standard three-quarter-inch line, features two power attachments—one for the shovel and one for moving the machine along the track—and does not require special trackage. Finlay is confident that his machine can be sold for roughly $1,200, significantly undercutting the $2,200 to $4,500 price range of other models.

(Between 1937 and 1949, Edwin "Burt" Royle received six patents for improvements to the loading machines he designed while working for Eimco. All were assigned to Eimco. John Finlay held two patents for loaders, both awarded in April 1933.)

(John Finlay died on September 30, 1935 at age 61, which might explain why his name was dropped from later references to the Eimco rock loader. Royle's name was usually not mentioned since he was an employee of Eimco, manufacturer of the machine and subsequent improved versions.)

Eimco Tractor-Loader-Dozer

The history of Eimco (Eastern Iron and Metal Company) crawler tractors spans a brief but highly innovative period from 1952 to 1965. Originating as a Salt Lake City mining equipment manufacturer famous for its underground "rocker shovels," Eimco leveraged its heavy-machinery expertise to design a lineup of commercial construction crawlers.

Eimco models completely broke the mold of standard tractor architecture by utilizing a forward-cab, rear-engine layout built on a rigid U-shaped steel tub chassis. They pioneered early versions of hydrostatic track systems, featuring independent power-shifting and torque converters for each track.

The military version was exclusively GM powered without a muffler, and the civilian version was mostly Cummins powered.

The Eimco Model 143 and Model 165 represented the final, most heavy-duty evolutions of Eimco's radical earthmoving lineup before they ceased tractor production in 1965. These machines were built to directly compete with mid-to-large-size conventional crawlers of the era, pushing the bounds of the company's signature engineering.

Despite their incredible power and unmatched blade visibility, the 143 and 165 could not overcome Eimco's lack of a commercial construction dealer network.

Eimco's line of tractor-dozers struggled in the broader construction market because their highly radical, rear-engine, forward-cab design was difficult for traditional operators to adapt to.

Several primary factors hindered the widespread commercial adoption of Eimco tractor-dozers:

Model 102 (Late 1940s – Early 1950s)

Model 103 (1959–1965)

Model 104 "Rocker-Shovel" (1951–1953)

Model 105 (1952–1962)

The Eimco Model 105 was rated at 143 engine horsepower, while the model variation often referred to as the 108 or its adjacent heavy-duty sisters (such as the updated 103/106 and 143/165 series) pushed output up to 158 to 160 horsepower.

Model 106 (Early 1960s)

Model 108

Model 123B

Model 143 (1960s)

The Eimco Model 143 was introduced as a rugged upgrade to the older 100-series chassis, offering a massive leap forward in hydraulic capability and framework structure.

Model 165 / 165B (1960s)

The Eimco Model 165 (and 165B) - The 165 series was the heavyweight powerhouse of the Eimco family, embodying the ultimate iteration of their forward-cab, rear-engine configuration.

Load-Haul-Dump

The Eimco Corporation introduced its line of rubber-tired, low-profile Load-Haul-Dump (LHD) machines for underground trackless mining in 1966–1967. These machines were built at Eimco's plant at 537 West 6th South

The emergence of these rubber-tired LHDs transformed hard-rock and coal mining eliminated the need for underground rail tracks, allowing machines to perform the entire cycle of scooping, hauling, and dumping.

While Wagner Mining Equipment pioneer-launched the articulated LHD concept in 1963 with the ST-5, Eimco—already famous for its rail-mounted compressed-air Rocker Shovel Loaders (like the iconic Model 12B)—quickly responded by developing its own line of diesel and hydrostatic rubber-tired LHDs.

In 1966, Eimco introduced the 900-Series of low-profile LHDs. Models like the Eimco 915 (5-cubic yard capacity loader; about 11 tons of coal) and the ultra-compact Eimco 911 (a 1-yard cubic capacity machine designed for tight 6×6 ft headings) were deployed extensively in metal, salt, and hard-rock mines globally by 1967–1968.

Eimco's early LHDs featured low-profile frames, no-spin differentials, high breakout forces, and early implementations of "EimcoMatic" hydrostatic drives, allowing variable speeds and high altitude maneuvering without power loss.

In 1971, two Eimco 915 LHD units (with 7 cu. yd. buckets) are put into service at a salt mine in Wyoming, described as a new system at the time. In 1972, two larger Eimco 920 LHD units (with 14 cu. yd. buckets) are ordered and put into service at the same salt mine.

October 1978
Eimco Mining Machinery Division introduced its new 918 Load-Haul-Dump machine for underground mines at the once-every-four-years International Mining Show put on by the American Mining Congress in Las Vegas, Nevada. (Salt Lake Tribune, October 7, 1978)

Summarized from the Salt Lake Tribune, February 25, 1979.

In addition to the 918 Load-Haul-Dump machine displayed at the Las Vegas show in October, Eimco Mining Machinery Division also had on display the company's 980 T-20 Truck, its 912 Load-Haul-Dump machine, and its 950 Tender (an underground bus). All of the machines had rounded contours, rounded bumpers and extra protection to protect miners and the machine during a rock fall event. Rocks that fall would be deflected off the machine by its contoured body. All of the machine also had ergonomic controls. The show attracted 32,000 persons from 50 countries. All of the display machines were sold on the spot.

Eimco also had manufacturing facilities in Great Britain, France, South Africa, and Spain, and joint ventures in India and Japan.

(The Eimco 918 Load-Haul-Dump underground truck was designed and styled by the team of Daryl Hatch and John Griffin, in their Salt Lake City design studio at 734 West 8th South. The same team had designed the DeLorean Snow-Cat being built in Logan, and Dresser's giant hydraulic excavator. - Salt Lake Tribune, December 19, 1982)

(The last advertisement in a local Salt Lake City newspaper for the Eimco Mining Machinery International Division was in February 1983.)

(There were Help Wanted classified advertisements showing the address of the Mining Machinery Division, 537 West 6th South, as late as September 1984. This was the location that built Eimco's Load-Haul-Dump underground truck.)

(After the closure of the Salt Lake City location, Baker Hughes moved production of the Eimco Load-Haul-Dump trucks to its plant in Fairview, Ontario, Canada, where production continued, culminating in the giant Model 920 with its 16-cubic yard bucket. Two larger models were planned for production soon. The location was known officially as the Eimco Jarvis Clark Division of Baker Hughes Canada. - Hamilton, Ontario, Spectator, April 27, 1988)

Timeline

January 1954
Model 105 was introduced. From the Salt Lake Tribune, January 20, 1954.

Perhaps the most important expansion in intermountain steel fabricating is under way at Salt Lake City's Eimco Corp. This pioneer firm and its affiliates, Structural Steel and Forge and American Foundry, is setting up production lines for a revolutionary earth mover known as the 105 tractor-loader-dozer.

It has required two years to develop the 105, which is different from any previous loading machine for which Eimco is famous, although it includes the same rocker-arm principle. Eimco has been building loading machines for many years and thousands of them are in use on construction jobs and in every mining community of the world. The 105 is a digger, loader and bulldozer in one unit.

Research and tooling up for the 105 involved an expenditure of close to $2-1/2 million and construction of a new 100 by 500-foot factory bay at the plant. Several hundred additional workers will be added to the present force of about 1,000 when production on assembly line basis gets under way late in 1954.

Joseph Rosenblatt, president of Eimco, and Morris Rosenblatt, who heads Structural Steel & Forge, report 30 engineers worked under Chief Designer Daniel M. Schwartz in developing the new machine.

The 105 is considerably heavier than Eimco's previous large model, and weighs approximately 34,000 pounds complete with loader. It has numerous design and operating improvements, many of which are exclusive in this type equipment.

Most important of these is Eimco's new Unidrive transmission, containing, in one compact unit, all of the gearing and clutches for speed changing and full independent reversal of each track. The design combines all the best features of torque converter, constant mesh gearing and hydraulically actuated friction clutches with sealed oil bath and pressure lubrication of all wearing parts. The oil-cooled, positive engagement clutches never need adjustment.

The new transmission makes possible independent control of each track. One can move for- ward and the other in reverse, providing maneuverability not possible in any other tractor.

Controls are simple. Two small, conveniently located handles immediately in front of the driver control all movements. The operator sits well up front for best visibility, and the power unit faces the rear and is located at the center of the machine. Units now in production use a 90-horsepower Diesel with matched torque converter.

The general fresh approach used by Eimco in the design and construction of the 105 suggests that there is a possibility of revolutionizing the field from a design standpoint and also with regard to efficient use of power as applied in tractor units.

July 1, 1959
Eimco Corp., Salt Lake City,employing 1,500 persons, announced introduction of a new-type tractor. The new 103 series tractor is a smaller companion to the larger and heavier 105 which introduced important engineering advances in field of crawler motive power. The new series will be available in the following basic units: Model 103, tractor and dozer; Model 123, front-end or fork lift; Model 113, specialized front end loader for steel mill use. (Salt Lake Tribune, July 2, 1959)

September 5, 1959
From the Deseret News, September 5, 1959.

New Eimco 103 Rolls Off Production Line - The first production unit of the new Eimco 103 line of crawler-tractors rolled off the assembly line this week at the Eimco Corp.'s Tractor Division in Salt Lake City.

It was a tractor-dozer with a hydraulic blade and is being shipped to Colorado Fuel and Iron Corp., at Pueblo, Colo.

The Eimco 103 line of crawlers, recently announced by the company is a 100 h.p. tractor, incorporating many unique innovations. In addition to Eimco's exclusive upfront operator position, for maximum visibility, the Eimco 103's are built with Eimco-developed unitized "stress flow" construction, whereby massive steel castings are scientifically molded to the shapes and stress patterns required for maximum strength and rigidity, without welds or bolts.

Another new feature is Eimco's "quadratorque," which, teamed with a heavy duty torque converter and "unidrive" transmission, permits four gear selections in either forward or reverse, allowing shifts from any speed, or from forward to reverse and back again, at any engine or tractor speed and load. The Eimco 103 is also the first tractor to incorporate a self-cleaning air cleaner, which utilized venturi action of the exhaust pipe to clean itself automatically.

A new modern assembly line, featuring the first tape-activated production equipment in the industry is being installed at the Salt Lake City plant for the production of the Eimco 103 line. The market for this smaller unit is much greater than the Eimco 105 and 106 units, which alone have taxed Eimco facilities to the utmost, so that additional production facilities and manpower will be needed to produce the 103 line in sufficient numbers to meet the demand already developed, according to a company spokesman.

Several Models - The 103 line will be produced as a bare tractor, six models of dozers, a front end loader, special steel mill front end loader and a log loader.

The Eimco Corp., with head offices in Salt Lake City, operates a Tractor Division, Filter, Process-Engineers, Mining Equipment and Metals Divisions from facilities at Salt Lake City, San Mateo, Calif., Palatine, Ill., and through Eimco affiliates in Great Britain, France, Italy, Canada and South Africa and maintains branch offices in all major regions of the United States.

Built In Utah - Every major component of an Eimco tractor, excepting only the engine and torque converter, is designed, engineered and built right here in Utah, where we have gathered an engineering, design and production staff second to none anywhere.

May 1, 1964
Eimco was awarded a $9,349,985 contract from the U. S. Marine Corps to furnish 382 Model 103 crawler tractors. (Deseret News, May 1, 1964)

January 14, 1965
Ogden Corporation subsidiaries other than Eimco. "Other subsidiaries include Avondale Shipyards, Inc., International Terminal Operating Co., Inc., Jarcho Bros., Inc. (contractor), Lipsett, Inc. (demolition) and Luria Brothers & Company (scrap metal supplier.)" (The Salt Lake Tribune, January 14, 1965)

(1965 - An online magazine article, without showing its source, states that in 1965, Eimco discontinued its line of tractor-dozers. This is most likely an error because Eimco was in the middle of its massive contract to the Marines, and the USAID contract for countries in southeast Asia.)

March 4, 1965
The Eimco Tractor Division was set aside as its own division, with 2,000 employees. Production of 426 tractors for the U. S. Marine Corp was progressing, with tests under way. Production of tractors was separated from loaders and industrial filters. (Salt Lake Tribune, March 4, 1965)

April 3, 1965
A follow-on contract for the Marines for 423 crawler tractors, reported as being worth $10 million. (Deseret News, April 3, 1965)

November 2, 1965
From the Salt Lake Tribune, November 2, 1965.

Mitsui Ship Building & Engineering Co. has started production of tractors and mining under license from the Eimco Corp. at its Yokohama, Japan, plant. The licensing agreement was reached several years ago. The new plant was formally dedicated on Oct. 19.

The plant will serve the Far East area, Eimco Corp. Tractor models and mining equipment will be exactly like that produced at Eimco's Salt Lake City plant.

The Yokohama plant will produce up to 200 tractor units yearly as well as mining machines to meet market demand. Highly competitive production costs dictated the decision to license Mitsui instead of attempting to supply the Far Eastern market from the U.S.

Photos

Eimco Photograph Collection at University of Utah -- A total of 268 photos of Eimco equipment and facilities.

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