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.
To achieve this, the companies agreed the follwowing:
"The undersigned companies are joining together to form a manufacturing and sales consortium for lathes
and hereby adopt the following resolutions:
Precision lathes will be manufactured with the following sizes (i.e. height of center above bed):
175, 195, 215, 245, 285, 325, 380, 430 and 480 mm.
The new standard lathes are to be designed and constructed with efficient features so that, as premium precision machines, they are superior to all competitors’ products through their solid construction
and reasonable prices.
The undersigned companies undertake to install in their factories the equipment necessary to implement the
above provision."
The sizes 175 to 195 mm and 245 to 325 mm were produced by Boehringer, the sizes 195 to 245 mm by Heidenreich & Harbeck, the sizes 325 to 380 mm by Franz Braun and the sizes above 380 bx Wohlenberg.
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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