The Internet Craftsmanship Museum Presents:

Ray Arden

Added to museum: 10/17/08

Early Engine Developer is Best Known as “The Father of the Glow Plug”

Few photos of ay Arden can be found. This one is from a 1939 issue of Popular Science. The caption reads: "Here Arden is using a cathode-ray oscillograph to measure the efficiency of one of his power plants. Such tests have shown that his latest product, which weighs only an eighth of an ounce, is more efficient, for cubic inch of cylinder space, than the best modern two-cycle motor-boat engines!" (Click on photo to view a larger image.) Photo: Popular Science


The following information was gathered from the Model Aviation Hall of Fame application submitted by Charlie Reich in 2004 and from other submissions from AMA members as noted. For a complete biography of Ray Arden, see on the Academy of Model Aeronautics web site. We felt Ray's significant contribution to model engines through the development of the glow ignition merited inclusion in this section.

No photographs of Ray Arden were available at the time of this writing. If anyone viewing this site has a photo of Ray or his engines, we welcome your submissions and will be glad to add it with appropriate credits to the photographer.

Biography of Ray Arden

Thomas Ray Arden was born in New York on February 24, 1890. Though a prolific inventor and innovator throughout his life, he is best remembered in the field of model aeronautics for not only his engine designs, but most importantly for his development of the glow plug ignition.

It seems Ray was good with his hands right from the start. It is reported he started making his own models of vehicles and boats at the early age of five, and by age eleven he had built his first rubber powered model airplane from magazine plans. However, his prowess with tools was not matched with good academic performance in Public School 63 in the Bronx, NY where he had to repeat some grades several times.

Viewing an early model engine changes the focus of his life

In 1907, at age 17 he attended a sportsman show in Madison Square Garden that would change his life. At the show he observed an early model aircraft engine developed by A.N. Herring who, like the Wright Brothers at the time was competing to be the first person to achieve powered manned flight. Ray studied Herring’s 2-pound gas engine, which was mounted in a miniature biplane. He stared at it all day long and would return many, often skipping school to do so. He would buy tickets or sneak in to stare at the motor and dream of building his own. At one point he got to talk to Mr. Herring and boldly informed him, “Someday I will make the smallest engine ever built.”

That year he did manage to make his first gas engine, and it weighed in at half that of Herring’s engine. Working in the family kitchen and home shop he also designed a revolutionary vibrating spark coil and condenser that weighed less than two ounces. To combat the characteristic high-speed miss of the jump-spark ignition, he used an early version of glow ignition which supplemented but did not replace the spark plug. In 1908, he designed and successfully flew a biplane powered by this engine.

A few years later in 1910, Ray designed a two-cylinder model engine weighing only fourteen ounces. Eventually, after 25 years of experimentation, he would be able to get the engine weight down to a mere two ounces.

In his biography of Ray Arden on the Academy of Model Aeronautics web site, Charlie Reich notes the following:

 “After graduation Ray’s career blossomed as an inventor with somewhere between 300 and 400 inventions sold through the 1920s. In the 1930s Ray formed a company called Ultrad Products to design and develop new products, primarily new toys in which Ray held a particular fascination. When a toy train manufacturer became interested in the possibilities of developing a miniature gas engine Ray was steered back to his natural field. A revolutionary valve-in-piston engine resulted and the Arden-designed Mighty Atom .097 ignition engine was introduced in 1939.

After introduction of the first Mighty Atom he continued to improve on the design and offered three additional progressively improved versions then called Super Atoms.”

Getting into the model engine business at the right time

From the entry of the United States into World War II in December, 1941 until the final surrender of Japan in 1945, the model business was pretty much put on hold. However, after the war ended, previously restricted items like methanol became available, and thousands of soldiers returning from the German and Pacific theaters were hungry for any recreational item related to flying. The market was ripe for model aircraft products, and inventor Ray Arden was in the right place at the right time. He immediately went to work and produced his revolutionary Arden .099 and .199 IC engines, which were introduced in 1946. Their light weight and compact size made them instantly popular with modelers.

Ray Arden with a home-made propeller on one of his engines. (Click on photo to view a larger image.) Photo: Popular Science

An accident leads to discovery of the glow plug ignition

At the same time, development of more potent fuels was under way. While Ray sampled over 500 blends of methanol based fuels, his friend Ed Chamberlin and Ben Shereshaw developed a hot new fuel Ed called “Liquid Dynamite.” By chance while testing some of this new fuel on one of Ben’s Bantam .19 engines Ben shut off the ignition and instead of stopping, the engine kept running. They physically stopped the engine and quickly removed the spark plug to find that the plug’s ground strap had broken and the center electrode was still glowing red hot, causing the engine to keep firing.

Ed immediately informed Ray of this exciting discovery, and both Ben and Ray started trying different glow plug designs. Ben’s first choice of wire for the electrode was Nichrome, which worked but burned out quickly. After experimenting with many different materials, Ray finally settled on a two-piece glow plug with a replaceable element made from platinum and iridium. When used with methanol-based fuel this element did not burn out.

At this point, Charlie Reich notes:

“Ray quickly introduced his second series of Arden engines, ceasing production on the clear plastic fuel tanks, which melted when using the hot new glow fuel. The 1947 engines offered the new, fuel impervious, black fuel tanks and the Arden engines were thereafter only offered in the ball-bearing version to take the additional stress and rpm’s created by the hot new glow fuel.

At the 1947 control line Junior Air Races in Cleveland, Ohio rumors started circulating that a man was selling a new gadget out of the trunk of his car. Word was that he had this “Gold Plug”—a replacement for our Champion Spark Plug, and that we could throw away our coils, condensers, points and batteries! Of course, it was Ray Arden with his new “Arden Glow Plug”, and modeling was forever changed! Ray Arden formally introduced the plug a month later at the Nationals in Minneapolis.”

In late 1947 or early 1948 Ray Arden transferred the rights for his glow plug to Ben Shereshaw. Ben then sold the Bantam engine manufacturing rights, spare parts and tooling to the OK-Herkimer Company. His agreement included a provision whereby he would manufacture the newly designed glow plug for them in his Miniature Motors plant to be sold under the OK-Herkimer brand name. The Miniature Motors plant soon started producing a line of new glow plugs known as OK brand XL Glow Plugs.

Ray Arden retired from the engine and glow plug manufacturing business in 1948, but in all probability continued to invent and design until his death in the 1950s.

View an article about Ray Arden from 1939

An article appeared in a 1939 issue of Popular Science magazine that tells more about Ray and his engines. CLICK HERE to view a copy of the article as a PDF file (16 MB—allow time to download). Our thanks to MECA (Model Engine Collectors Assn.) member Eugene Ethier for the donation of the magazine to our library museum.

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The following note on the unfortunate fate of Ray’s engine tooling comes from Victor G. Didelot courtesy of Tandy Walker:

“Ray Arden passed away in the early 1950s, while still living in Danbury, CT. After Ray’s death, his wife retained all of the Atom and Arden tooling for several years. However there was an unusual Connecticut law enforced at that time that required her to provide semi-annual financial statements to the state. Even though the engines were no longer in production, this was still a requirement because she owned the tooling that could produce these engines. To put a stop to this difficult task of providing these financial statements each year, she had all of the Atom and Arden tooling destroyed. Shortly thereafter, the state of Connecticut did away with that law!”

Arden engines (Click on any photo to view a larger image.)

This Arden .099 ignition engine was donated to the Craftsmanship Museum in Vista, CA by Donald Holcomb. The engine was designed and introduce in about 1945, right after the end of World War II to a public eager to go model airplane flying. The donor included the ignition system as well, so Tom built a display stand for it complete with the ignition components. When we got them, they were still attached to what was left of the original bulkhead from a plane last flown long ago.
This is the Arden .099 engine in glow plug form. A lucky discovery led to the development of the glow plug, for which Ray Arden is better remembered than for his engines. This engine was also donated by Donald Holcomb and like the one above is also on display in the Craftsmanship Museum in Vista, CA.

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