Zerbe builds scale model steam engine

By Caroline Rosacker

Prior to the invention of the gasoline-powered engine, mechanical transportation was fueled by steam. The concept of a steam engine actually pre-dates modern engines by a couple of thousand years. Throughout the years a number of leading scientists have investigated the idea of using the force generated by heating water to power machines. The real groundwork for the development of a practical, working motor didn't come until the mid-1600s. It was during this time that several inventors were able to develop and test water pumps and piston systems that would pave the way for the commercial steam engine. Thomas Savery, Thomas Newcomen and James Watt all made significant contributions to the efficiency and design of the steam engine. Watt's engine would eventually become the dominant innovation for all modern steam engines  and would help bring about the industrial revolution. 

Background information

Jim Zerbe, a city employee, has recently put the finishing touches on his first attempt at building a scale-model steam engine. Jim and his wife, Cori, moved to Guttenberg following retirement in 2005. Jim has been employed as the city's south marina caretaker for the past several years. Zerbe told The Press, "Several years ago Russ Loven asked if I would be interested in helping out at the newly-built south marina complex. Because of my interest in boating, ownership, and operation of a 32-foot trawler on the Mississippi River, I decided to take him up on the offer. I have enjoyed working there ever since." 

Zerbe, who has had experience with airport management, added, "A marina, like an airport, is a valuable, and expensive asset to a community. It is important to keep it preserved and functioning to its desired purpose. I really enjoy working with the city workers and try to help out whenever possible." 

Education and inspiration 

Zerbe grew up on a dairy farm in Hortonville, Wis. He attended college at the University of Wisconsin, Madison earning B.S. degrees in agriculture and in mechanical engineering. He later earned his MBA degree from Edgewood College in Madison. 

He said, "It was at the University of Wisconsin where I took my first basic machining course, piquing my interested in metal work.  I did a couple of small projects for the course and worked for the agricultural engineering school in the shop for a couple of years furthering my interest. After graduation I did a three-year stint as plant engineer for a company in California. I was later hired at a machine shop in northern Minnesota doing control circuitry for high-speed packaging machines. During that time, I hung around with the shop guys and picked up a lot of information on machining and was able to use the equipment for different projects."

Interest in aviation

"I farmed for eight years in southern Minnesota, but was still interested in metal work. I built a fully-equipped machine shop and started building an airplane. I became interested in aviation – left the farm and bought a Fixed Base Operation (FBO) on an airport in Lone Rock, Wis.," he shared.

With access to an equipped shop, Zerbe was able to pursue his flying and aircraft mechanic ratings. An opening in the aviation department of the Wisconsin Department of Transportation (WDOT) became available, and Zerbe was hired as a transportation engineer and pilot with the state. "I flew for the state for 15 years and managed construction projects at many of the state’s airports," he noted.   

Scale-model steam engine

"With extra time after retirement, and my shop here in town, I started looking into building a model steam engine. There are several organizations that cater to these interests, and there are lots of building options and parts available. A couple of years ago I found some old plans for a boat steam engine in a magazine and started the project. I learned very fast that I didn’t have the equipment or machining skills necessary for the project and had to abandon it." He continued, "I acquired a bench lathe and precision drill mill, and spent some hours making chips until I felt ready to start again. My equipment is 20 years old, made in Taiwan. It is lighter duty, but adequate when working with the small steel and brass parts for the engine. It just takes more time and smaller cuts. I bought what is called a casting kit. It contains the necessary rough steel, brass castings, bar stock and construction drawings for the project."

Zerbe started his scale-model steam engine project last September and finished this year in April. He commented, "I would estimate three or four hundred hours were involved, but a lot of it was a learning process and trying to do things right. I think the project came out well considering it was a learning experience and my first one." 

Zerbe is pleased to announce that the engine started the first time it was hooked up to air pressure. He explained,  "In the order of engine construction it is recommend to build a steam engine first, as its tolerances are more liberal and the valving less complicated. They recommend building a simple gas internal combustion (IC) engine next. I have started the second engine. This one will be gas – built completely from bar stock without any castings.  If it is successful, I will then build a more complicated engine from another casting kit."  

I asked Zerbe, "What does one do with a scale-model steam engine?" He answered with a laugh, "So, the question is, what do you do with a model steam engine after they are constructed?"