In the mid 1920s the Czechoslovak Tatra company established a German subsidiary company to manufacture Tatra 11s and 12s for the German market. The company was called Deutsche Licenz Tatra Automobile, or DELTA for short. DELTA assembled knock-down kits of standard Tatra cars and a small number of commercial vehicles. DELTA however would not enjoy an exclusive license for long, as by the early 1930s at least three other companies began manufacturing Tatra cars in Germany under license. The first of these was Rohr.
Rohr Auto AG was founded in 1926 in the city of Ober-Ramstadt. The company's principal was Hans Gustav Rohr. Hans had little interest in pursuing the family business in lead smelting but was fascinated with the new technology of heavier-than-air flight. In 1912, at the age of 17, he designed, built and flew his own aeroplane. When the Great War started he enlisted as a fighter pilot, but after completing his formal training, his engineering skills were recognized and he served out the war working on aircraft projects.
With Germany banned from building aircraft by the Treaty of Versailles, Hans Rohr turned his focus to automobiles. Between 1919 and 1924 he developed several prototypes which made use of his experience with aircraft design, but no established manufacturers were interested in his designs. This only encouraged him to found his own automobile company, in partnership with investor, Hugo Greffenius. In October 1926 they took over the insolvent Falcon Automobilewerke in Ober-Ramstadt and began building a new car to Rohr's designs.
Rohr's first car, the Rohr 8, was formally unveiled at the Berlin Motor Show in 1928. The car featured lightweight construction, low-slung box frame chassis of sheet steel, rack-and-pinion steering and independent front and rear suspension, which were all pioneering features for the time. Motor-Kritik's acerbic editor-in-chief, Josef Ganz, was lavish in his praise of the exceptionally good driving characteristics of the Röhr 8, unmatched by other contemporary vehicles. Rohr quickly gained a well deserved reputation as the manufacturer of high-quality, technically advanced automobiles, but as with so many German small manufacturers, production rates was slow and when the Great Depression hit in 1930, the company fell into bankruptcy.
After a short interval, a new company, Neue Rohr AG, was established to take over Rohr Auto AG. Hans Rohr and his technical team however, left the company and moved to Adler where they helped design a series of advanced vehicles, culminating in the streamlined Adler 2.5 litre Autobahn of 1937. Production of the Rohr 8 slowly recommenced but given the straitened economic climate, it was obvious the company needed a smaller, cheaper car on the market if it were to survive.
Tatra T75
Meanwhile, over in Koprivince, Czechoslovakia, work was progressing on a replacement for the Tatra T54. The T54 was the larger cousin of the of the revolutionary T11 and 12, but powered by a larger four cylinder air cooled engine. The T54's successor would be the Tatra Type 75, powered by a four cylinder air-cooled engine of 1688cc capacity and wrapped in a modern styled body. The car was unveiled in 1933 at the Prague Auto Saloon. A little over 4,500 T75's would be built over the car's 5-year production run (1933-1938).
Rohr Junior
Back in Germany, Rohr were attempting to develop a budget car offering suitable to the market, but progress was hampered by the loss of Hans Rohr and his engineering team. To speed the process, the company's new management decided on the licensed production of an existing car, but what to choose? Certainly not anything from one of Germany's leading manufacturers, who doggedly persisted with out-of-date designs. However, Neue Rohr recognized in Tatra a shared vision for advanced design so the two companies entered into negotiations and a deal was done for Rohr to manufacture the Tatra T75 under license.
Unveiled at the 1933 Berlin International Motor Show, the Rohr Junior was not a direct copy of the Tatra T75. Rohr had redesigned the Tatra body, making it a little more square and ungainly than its template. Under the Rohr skin however, was Tatra's signature tube chassis, independent four wheel suspension and air-cooled engine. The car received positive reviews from the Motor-Kritik.
The contemporary photos above belong to Michael Schlenger from his wonderful Vorkreigs-Klassiker-Rundschau blog https://vorkriegs-klassiker-rundschau.blog/2019/06/11/einst-auffallend-praesent-roehr-junior-10-30-ps/
At the 1934 Berlin International Motor Show, Rohr showcased an improved Rohr Junior and Rohr 8. Motor-Kritik wrote:
"The new Rohrwerkes, whose negotiations over the joint venture with NAG have apparently been delayed, still appeared at the automobile exhibition as a purely independent company. You can't deny the factory management an enterprising spirit. In addition to improvements to the 1.5 litre Rohr Junior, whose air-cooled engine is said to have become quieter, more flexible and more economical. The plant will also be showing a new high-performance car that is said to have a top speed of around 140 km. The 3.3 litre eight-cylinder car, designed by the Porsche design office and already well-known from the large test car, equipped with a compressor for [testing] purposes. In order to meet the car's intended purpose - high-speed motorway traffic - the car’s chassis and frontal aspect has been set as low as possible. The low slung, hollow box frame has now been given cross beams, which are welded very closely to the long girders, so that the greatest possible torsional rigidity of the frame is achieved. A brand-new feature of this type is the transition to the Porsche axle with torsion bar suspension, which allows the spring action and damping to be precisely balanced."
The Motor-Kritik article touched on an important point - the negotiations with NAG for a joint venture. In 1933, Rohr had been struggling financially, a situation that was not helped by the coming of the National Socialists to power that year. Restrictions on Jewish finance led Rohr's Swiss backers to withdraw their investment, leaving the company virtually insolvent. Negotiations commenced with NAG for a merger, but before they could be concluded, Rohr was declared bankrupt in March 1935. At best, only a few hundred Rohr Junior's were built. Stoewer of Stettin would purchase the T75 production license along with all machinery from the receivers. Before 1935 was out Stoewer would have their own versions on the market as the Stoewer Greif Junior.
For more about the history of this rare marque: http://roehrauto.de/index.php
German Licensed Tatra manufacturers:
DELTA/DETRA: https://tatrat600.blogspot.com/2021/05/deutsche-license-tatra-automobile-delta.html
Stoewer Greif Junior: https://tatrat600.blogspot.com/2021/10/1935-stoewer-greif-junior-tatra-under.html
NAG-Voran 220 - https://tatrat600.blogspot.com/2021/10/1933-nag-voran-220-630-ps-tatra-under.html
