The Panzer Tractor Through the Years

A brief history of the Panzer tractor, built by Copar


| May 2013



Panzer Ad

An early advertising flyer for the Copar Panzer 8-1/2 hp tractor.

Illustration Courtesy Sam Moore

Awhile back someone sent me the following note: “Enclosed is an ad for Copar tractors. I have never heard of a Copar and I am 77 years old.” The ad, from an area shopping paper, reads: “For Sale, antique tractors, Copar Panzars, Pennsylvania Panzars, Copars, all restored, all have engines.” As anyone familiar with the well-built little Copar garden tractor knows, the name should be spelled Panzer, just like the German army’s armored forces in World War II.

Looking for a better way

The story of the Copar tractor goes back to a hot summer day in 1953, when James A. Clark was trying to put in the lawn around his new home in College Park, Md. Clark had rented a walk-behind tractor with attachments but was making little progress and having to work way too hard. Clark happened to be chief engineer at the Ahrendt Instrument Co. in College Park, a firm that developed and built precision electronic and electro-mechanical navigation and gun control devices. Combining an engineer’s approach with that of a lazy man, Clark determined that there must be an easier way to put in his lawn, and a riding tractor was the answer. After checking out a number of the riding machines then on the market, he came to the conclusion that none were up to the job and he could design a better one.

The owner of Ahrendt Instrument Co. gave Clark the go-ahead to use company time and facilities to design his new garden tractor. By the end of 1953, a prototype had been hand-built. Ahrendt employees held a contest to name the tractor and “Panzer” was the winning entry. The machine was exhibited at the Garden Supply Trade Show in New York in early 1954. Apparently the Panzer got a lot of attention at the garden show, and Ahrendt made the decision to start building garden tractors, a business completely foreign to its precision instruments line.

Copar (based on the name of College Park) was formed to handle manufacturing. The first Copar Panzer tractor was delivered to a Virginia dealer in July 1954. However, the manufacture of precision instruments and tractors didn’t co-exist very well and a new facility was needed. A long-vacant mill in Laurel, Md., was purchased and renovated. The new Copar plant opened there in January 1955.

Glidamatic transmission

The first Panzer was a 3-wheeled machine with an 8-1/2 hp Briggs & Stratton engine that drove a salvaged Dodge or Plymouth cut-down car rear end through a drive system the company called “Glidamatic.” Plymouth brake drums and shoes, each operated mechanically by a foot pedal, were used to give individual rear wheel brakes. Copar bragged that, “The Panzer tractor’s combination of clutchless, instantaneous forward and reverse action plus exceptionally short turning radius plus individual rear wheel brakes make it the most maneuverable tractor in the field.”

A hand lever at the right side controlled the Glidamatic power transmission system (a simple belt-tightening mechanism and friction-pulley reverse); push forward on the lever and the tractor moved forward, pull back and it went backward, with neutral in the middle. Three forward speeds were available, but shifting between them required stopping the engine and moving a V-belt between three sheaves of different sizes on the engine pulley and the drive pulley. When the shift lever was pulled all the way back, drums on each pulley came into contact with each other, giving the friction drive reverse. The machine was 70 inches long, 43 inches wide at the rear wheels and weighed 600 pounds.