In 1928, the four lathe manufacturers
joined forces and founded the manufacturing and sales association “Vereinigte Drehbankfabriken” (VDF, "United Lathe Manufacturers") in order to develop and market the "Einheitsdrehbank" (standard lathe) in several sizes.
After WW II, only three of the four companies were left, as Franz Braun AG in Zerbst was located in the Soviet occupation zone and and was transferred to public ownership in 1946.
Beginning at the end of the 1960s and then much more in the 70s and 80s, the German industrial landscape started changing. Numerical control was introduced. With the sale of Heidenreich & Harbeck to Gildemeister in 1972, only two of the VDF companies were left. Gradually, Boehringer remained the only manufacturer in the VDF, even though the successor companies to Wohlenberg and Franz Braun still exist today.
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