Grenning Models

Reliving the Historic Internal Combustion Engine Era

The Otto-Langen Atmospheric Engine

History of The First Project

By the early 1980's large numbers of historically significant engine models began appearing at shows and gas ups. With only very small numbers of nineteenth century and early 20th century engines surviving, the probability for a collector acquiring an engine of choice has become more and more remote. The reality of two world wars and a century of progressing technology have forever-sealed demand to be greater than availability. By the '90s it became clear that for the average enthusiast affording an example of the rarest pieces was practically impossible. In response, models of significant engines began to appear. Collectors who were machinists decided to copy "in miniature," engines not available otherwise.

At this point in 1990, Grenning Models was founded by accepting the challenge of creating the first working model of the most significant 19th century internal combustion engine. It would be a replica of the 1867 vertical, fluted Grecian column engine developed by Nicolaus August Otto and Eugen Langen. Otto was the engineer while Langen was the investor. They called their machine an "Atmospheric Gaseous Engine" or in German, "Atmosphariche Gaskraft Maschine."

Plate showing original Otto-Langen developmental engine

Revisiting the challenges and innovations accomplished by Otto in the primitive 1860s was a humbling revelation. Creating a functional replica of Otto's original effort would be a very worthy undertaking. To this day his contribution to the industrial revolution remains the foundation of our petroleum-based civilization. However, for a model maker the challenge of creating an acceptable version in miniature would require overcoming an entire series of hurtles. Not only would it have to function but, it would have to run at "scale speed." That meant being capable of operating with a dignity of RPMs in relation to the original and not as some high-speed whirly-gurgle toy oddity spinning wildly.

Did original engineering information even exist? If so, where would it be? Would engineering principles function in model scale? Could a scaled prototype model be developed as a path to multiple production?

Available information was only to be found in about a dozen 19th century English, German and American volumes long out of print. A 10-year effort finally procured most of these works. In addition, in 1990 an ad was placed in "Gas Engine Magazine" asking for correspondence from readers who had knowledge of the "Otto/Langen Atmospheric Engine." One solitary gentleman responded. He turned out to be an astute professional scientist, life-long collector of internal combustion engines and an astounding individual. Through his very generous guidance and encouragement the trail to the acquisition of original engineering documents was opened. After a long and interesting search, the original hand written and drawn, German Patent for the Otto/Langen atmospheric engine was located in the library of a major American engineering college. It was in "old style German scientific syntax". An English translation was completed with the aid of an engineer specializing in the translation of that syntax. - Finally, a useable English language copy of the patent along with the original drawing was in the possession of Grenning models. With that information to digest, a full developmental understanding of the Otto/Langen atmospheric flame ignition cycle became possible.

In addition to the engineering research an original full sized Otto-Langen engine was studied. A spectacular, original example is in the care of the "Rough and Tumble Engine Association" at Kinzer, Pennsylvania. It is over 8 feet tall, and runs on hydrogen which is similar to the original fuel called "producer gas." It is the oldest internal combustion engine in the Western Hemisphere and one of three or four surviving examples in the entire world. Most collectors consider it a priceless heirloom icon of industrial heritage.

To develop a model it was determined a mechanical prototype would be necessary as a first step. Its purpose would be to affirm mechanical and engineering principles in miniature scale. Its visual appearance would have no relationship to the finished model.

Photo of  the mechanical Otto-Langen prototype

The only similarity would be a similar size to the projected model. True to form the original prototype was indeed very crude with almost no similarity at all to the eventual model. However, through the prototype testing program miniaturization of the atmospheric cycle was reached.

Hydrogen was the first fuel tested in developing the prototype model. One very unique characteristic is its ability to burn easily in almost any ratio with the atmosphere. Actually, hydrogen worked extremely well in testing. But, it can be a tricky gas requiring great care. To avoid any Hindenberg reenactments other gaseous fuels were explored for miniature application. Two additional fuels were tested extensively, propane and acetylene. In the end it was discovered all three gases worked well, but acetylene would standout as the most logical for use in a small model of this design. Ready availability, inexpensive cost and modest equipment for regulating pressure, all suggested acetylene.

Once all research and mechanical prototype development was completed a 1/7-scale version of the original full-size engine was created for transfer of the confirmed miniaturized operational principles.

Photo showing Grenning Models 1/7th scale Pre-production prototype

After a period of intense effort a pre-production model of the engine was created that was capable of functioning at true "scale speed." Shortly there after about two dozen Otto-Langen atmospheric models were built and sold. Ten years later they continue to be displayed and run at events.

Since that time Grenning Models has produced the Otto-Langen engine in 4 different scales. The first was a 1/7th, then a 1/14th and 1/6th, and most recently a 3/4-scale version. This latest version is seven feet tall, weighs 650 pounds and functions with true flame ignition like the original.

Grenning Models 3/4 scale Otto-Langen

Being shown early 2000

It is available on special order for institutions, societies and collectors. For details regarding this astounding accomplishment and availability contact us directly.

1/2 Scale  1 HP Springfield Type "A"

This was the first four-cycle engine offered by Grenning Models. It was chosen because the innovations of the Springfield Company were visionary. The firm's successful development of the overhead camshaft - side shaft combination and fuel injection in 1896 was prophetic. More than 100 years later millions of automobiles have engines using these same original principles. Aside from Otto's engines few other contributions to the technology can match Springfield. The version we modeled is a 1/2 Scale replica of the 1 H.P. example displayed at the Coolspring Power Museum at Coolspring, Pennsylvania.

In their final form all detailed and assembled versions were fully prepared and tested in our shop before placement. In delivered configuration, function is fully operational at scale speed. As a result, sales of this museum quality model were spontaneous and global. An amazing 30% went to customers who ordered 2 or more models!

In order to maintain the highest quality standards, all Grenning models are assembled by one pair of hands in Lockport, New York. There are no overseas subassemblies foreign labor, or farmed out "cheap work" involved with these creations. As a result, collectors and institutions "wait" patiently for their models to be built in their turn. All models are assigned on a first come first served basis.

Long after production the Springfield model has become one of the most desirable offerings in the hobby. As with this engine, an owner of any Grenning model receives a detailed, registered, personalized owner's manual. In addition, every model is serial numbered and retained in our records.

The Springfield model has been acclaimed as the best completed historical engine model ever available to the public. In the August 1999, edition of "Gas Engine Magazine," a review of the Springfield by Woody Sins, simply says there is nothing like it. His quote is, "it blows them all away!" In addition, "Popular Mechanics Magazine" recognized the Springfield as "Stanley Project of the Month" in its January 1997 edition. For the lucky owners there is simply nothing like it!

Photo showing production version of the 1/2 scale 1 HP Springfield

Specifications:

Flywheels 13"

Overall height, 18"

Weight Approximately 140lbs

Speed Scale Speed operation of 150 to 500 RPM!

Governor - Fly ball, (fuel and inlet valve interruption)

Coolant System Tank - (Brass tank thermo-siphon)

35 castings of iron and brass

Color - Brick Red

Base - Satin Urethane finished Oak

Cylinder bore 2.00"

Stroke 2.5"

Overall Length 36"

Twin Cylinder Springfield

In 1997 to celebrate the Centennial achievements of the firm and to promote the Springfield model, a twin cylinder version was built. This was displayed at the National Association of Model Engineering Society Exposition, in Detroit, Michigan and at the Cabin Fever Model Engineering show held at Reading, Pennsylvania. Its creation was not intended to be a commercially available model. However, after its initial display demand was strong enough that a limited number have been created. Interested parties should contact the maker for availability.

Twin Cylinder Springfield

The Alexis de Bisschop Engine

A model engineering first - flame ignition

In between Nicolaus Otto's atmospheric engine and his four-cycle engine there was another development. It was the work of Alex de Bisschop and like Otto's atmospheric engine it was fired by flame ignition. By 1870 he was offering his contribution in power ratings of one manpower to five manpower. As a continuing step in the development of internal combustion it offered many advantages among very serious faults. On the positive side were its low cost, great simplicity, minimum floor space and absence of water-cooling. On the negative side was its appalling inefficiency. It burnt 11 cubic feet of gas per hour under full load.

Andrew, Ltd. of Stockport, England was a major manufacturer of Bisschop engines. The smallest version operated in the 70 to 145 RPM range. More than 2,000 units were built.

Bisschop engine in Manchester England

In 1882 the Sombart Engine Co. of Hartford, Connecticut licensed the Bisschop. Only a hand full were ever manufactured because by this time continuing improvements in internal combustion made the Bisschop cycle obsolete. The Sombart is among the most rare of industrial revolution artifacts! Worldwide only one engine survives.

5 manpower Sombart owned by Tom Stockton

Grenning models chose to create a 1/5th-scale version of the 5-manpower engine. At the start of the Sombart project there was no known contemporary operational small-scale model of a flame ignition internal combustion engine. Since a candle flame is not scalable in proportion to a small model the challenge was to engineer a workable version of the original.  Again, a small-scale mechanical prototype version was developed.

Mechanical Prototype

Over an extended period of time it was tested and refined. For the first time known a true scale model of an internal combustion engine with operational flame ignition was created. It was the only model ever offered by Grenning Models as a kit.

Sombart Production at Grenning Models

Purchasing a Grenning Model

Large numbers of models representative of the historical development period of internal combustion are available to the public. They range in price from under one hundred to many thousands of dollars. We are often asked if owning the best model examples are a good investment. Our answer to that question is always - one should purchase a model because it is enjoyed. We like to see enthusiasts acquire models because they are meaningful for the owner. We encourage people to take them to events for display and sharing among friends.

Many are surprised that our models are built in finite numbers in spite of continuing market demand. After a specific number of units are prepared the patterns are retired. In this way we are able to be in a position of continual development. Currently, three new engines of fundamental historical significance are in development. They will be announced shortly. Our models are not just scaled down versions of originals. Rather, through the use of state of the art CAD software, strenuous prototype development, and state of the art CNC equipment our internal combustion models function at true scale speed. We think they are second to none!

To be fair, we must point out that our models do retain their value. We know of no case in the few numbers sold in the secondary market, where the value was not significantly above the original purchase price. However, our models are intended for true enthusiasts rather than speculators.

PHOTOS OF OWNERS RECEIVING THEIR SPRINGFIELDS

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