Siemens 2 PS Bodenfräse (Boden = soil), the first walk behind model of Siemens, 700 machines were built from 1920 till 1924. The two stroke benzol engine was made after the "Grunder" system, weighed 55 kg, had 500 cm3 piston deplacement and 3 - 3½ hp, and was manufactured by the Siemens Blockwerk. The Bodenfräse had 2 forward gears of 0.93 and 1.87 km/h and a total weight of 170 kg.
For more information on the Siemens & Halske Blockwerk and their other factories, see www.siemens-stadt.de.
The Siemens 4 PS Gartenfräse (Garten = garden) followed the 2 PS model in 1924. The Siemens Blockwerk made it's four stroke petrol engine with 90 mm cilinder bore, 110 mm piston stroke, 500 cm3 and a weight of 84 kg. The crankcase consisted of two aluminium castings, the cilinder was air cooled and provided with vertical cooling ribs. On top of the engine was an aluminium casting containing the cooling ventilator, blowing the air down along the cilinder's cooling ribs. The intake and exhaust valves were fitted in hanging position in the cilinder head. During 1924 and 1925, 200 of these Gartenfräse tillers were made.
Siemens Gartenfräse K1, with a 4 hp 4-stroke engine. This engine has the cooling fan behind the cylinder, which carries horizontal cooling ribs.
This K1 is on display at the Deutsches Landwirtschaftliches Museum in Hohenheim.
The Siemens Plantagenfräse S8 (Plantage = plantation) had an 8 hp water cooled two stroke engine, and was made from ca. 1925 till 1927. Working width 90 cm, 20 spring tines with 470 mm diameter, rotating at 200 rpm. Two forward speeds of 1.08 and 2.16 km/h. The tractor weighed 360 kg.
I know of two of these, one in Holland and one in Germany. I am not sure if Siemens made them theirselves under license, or just imported them from Switserland, as it is exactly identical to the SIMAR No. 10.
SIMAR Leichtfräse C2 (Leicht = lightweight), imported into Germany by Siemens-Schuckert because they lacked this size of machine theirselves. The small 2-stroke engine developed 2½ hp, weighed 108 kg and drove 1.1 or 1.3 km/h (dependent of the size of wheels). Working width was 35 cm, almost a hectare could be cultivated daily. The C2 sold for 980 Reichsmark in 1928.
Siemens Kleinfräsen K4 and K4-A (Klein = small), 4 hp two stroke petrol engine model 92068-0FM2, ca. 1925-1927. Working width 70 cm, 12 spring tines with 500 mm, rotating at 210 rpm.
These seem to be some sort of conversions from the Siemens K4, probably made in Switserland. No further details available.
Siemens Kleinfräse K5 and K5-4, 2 stroke petrol engine, developing 5 hp at 1500 rpm. The K5 had engine model 92168-1FM2, the K5-4 had engine model 3FM2. Made from 1928 till 1935, Siemens was able to sell around 5000 of the K5. Fuel consumption 3 - 4 litres/hour. Working width was max. 70 cm, with it's speeds of 1 and 2.5 km/h the K5 could work 600 or 1500 m3/hour. With use of rubber street rings, a speed of 5 km/h could be reached for transportation purposes. The machine weighed 250 kg and cost 1630 ReichsMark in 1928.
The carburettor was a SUM KMH 32. A difference between the K5 and the K5-4 is that the K5-4 did no longer have a removable cover above the clutch, meant for lubricating. The engine bore and stroke are 90 x 95 mm.
With many improvements, this tiller's manufacture was continued by Bungartz until ca. 1945.
