Oversight of all Siemens tiller tractors, built from 1912 till 1930 by Siemens-Schuckert in Berlin, Germany
First prototype of Siemens rotary cultivator, constructed in Siemensstad (near Berlin) in 1912, under supervision of Konrad von Meyenburg and professor Holldack. It had a 2 cylinder 2-stroke Gray (USA) paraffin engine, 12 hp at 700 rpm and weighed little over 1000 kg, while working width was 150 cm. The same tractor was also made with an electric motor, this is shown on my electric powered machinery page.
From 1913 the American engines were replaced by 25 or 50 hp Kämper petrol engines, these were placed in line with the forward direction.
This first model of Gutsfräse (Gut = estate) was made 1914/15 in Greifswald, according to directions of the Siemens-Schuckert-Werke. It's four cylinder petrol engine was manufactured by the Siemens Blockwerk. It had 90 mm cilinder bore, 150 mm piston stroke and an output of 25 hp.
50 PS Siemens petrol powered cultivator, developed during 1915, 200 cm working width. This four cylinder engine was also constructed by the Siemens Blockwerk and was rated at 60 hp with 120 mm bore and 180 stroke. The tractor was equipped with a compressed air starter at the front of the engine, backupped by a manual starting device at the side, connected to the engine by means of conical gears. Because of a policy change at the department of the Siemens Autowerk (car works) which manufactured the Gutsfräsen, only 4 of these were made.
For more information on the Siemens & Halske Blockwerk and their other factories, see www.siemens-stadt.de.
30 hp petrol powered Siemens Gutsfräse G2, 130 cms working width. The engine was a 30 hp Kämper engine.
During 1917/18 35 hp Gutsfräsen were made by the Siemens Dynamowerk (generator works). These were powered by four stroke Blockwerk-engines model D, with 95 and 146 mm bore and stroke. The engines were rated at 44 hp @ 1700 rpm.
Siemens Gutsfräse G3, 1924-1928. Working width was 160 cm, total weight 2800 kg. The tractor has three forward speeds of 1.6, 2.2 and 3.8 km/h as well as a reverse gear of 1.6 km/h. The tiller attachment could rotate at 150 and 180 rpm, and was equiped with 54 spring tines. Working width could be enlarged to 200 cm, then using 78 tines. At first, Siemens used a 4 cilinder 4 stroke made by Deutz-Oberursel, 38 hp @ 950 rpm when running on benzol, but it could also run on petrol, Tetralit or other spirits mixtures. Due to engine problems, they later used Kämper engines with 35-40 hp. Sales brochures advertise the tractor as "30 PS G- oder Gutsfräse".
Production of the G3 was ceased in 1928-1930 because all production capacity was requested for making enough Kleinfräsen K5. Another reason was that the G3 was not equal to the tough conditions in Russia, where most of them were sold to.
In 1926 4 twin cylinder engines with 94 mm an 140 mm bore and stroke were manufactured for use in the Siemens Bauernfräse (Bauer = farmer). These engines were rated at 20 hp @ 1500 rpm and weighed 197 kg. One of the four was converted into an oil engine. It used a Bosch injection pump "AKRO" with air storage piston. This fuel injection system proved to be unsuccesful, the same probably applies to the tractor itself: it had been under construction since 1923, but I have found no mention of it in any sales literature.
Siemens Großfräse G4 (Groß = large), built from 1929 till 1930. Weight 2600 kg. Powered by a 4 cylinder Kämper engine, either run on petrol or paraffin (model G4P). Power was 35 hp at 1050 rpm, the tractor had forward speeds of 1.6, 2.2 and 3.8 km/h as well as one reverse gear. Working width 160cm, 48 spring tines with 80 cm diameter, speeds were 150 rpm for normal tilling (0.2 hectare/hour) and at 180 rpm for light cultivation at a higher forward speed (0.5 hectare/hour).
Reason for the new model designation was that the gearbox, tiller attachment and mechanical lift had been strengtened in order to handle the hard conditions in Russia, where it was used to cultivate swamps and waste land. Also, the G4P's carburettor was specially adapted for use of low quality Russian kerosine.
The Siemens G4 shown at work. The price for this tiller was 12,000 ReichsMark in 1928, one of the reasons for failing sales and end of production in 1930. One other reason was that the Siemens were only very limitedly applicable for other purposes than tilling.