National Amusement Devices

National Amusement Devices in Dayton, Ohio was founded in 1919 as the Dayton Fun House by Aurel Vaszin. Based on research, they built a 2-foot gauge miniature train that could be either gasoline or electric powered. This resembled a typical standard-gauge center cab electric train as early as 1922. Vaszin was an early environmental idealist and really pushed the idea of electric powered trains, as safer and less polluting.

A young mechanical engineer by the name of Frank Williams joined the Dayton Fun House in the mid-1920s, and later so did his dad and his son. They greatly improved on the concepts that had been previously developed. After World War II the Fun House began attracting worldwide recognition, and supplying amusement parks elsewhere. They changed their name to "National Amusement Device Co." (or NAD) and operated under that name for three decades.

They designed some of the popular early miniature trains used in amusement parks around the country. Their most popular and recognizable model was the "Century Flyer", supplied to various amusement parks and for children's rides. From the 1940s to the 1960s, NAD also built some full-size rollercoasters, many designed by John Miller. These were mostly wooden, and as of 2010 most no longer exist.

In addition to building trains and components for amusement parks, NAD also built entire rides, including some unique roller coasters. As of 1959, they claimed to have built more than 400 full roller coasters.

Some of their famous rides include:

NAD was sold to Bill Roose, son of George Roose of Cedar Point, in April 1973. The name was changed at that time to International Amusement Devices Inc, based out of Sandusky, Ohio. From this point on they specialized in park design and brokering rides. Vaszin stayed on as a consultant until his death in 1979. IAD was later run by Eugene K. Feerer.

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