The maker of the strange-looking but highly effective PeTeWe PFS-4U projection form grinding machine was "Werkzeugmaschinenbau Prazisions-Technik GmbH", a company founded and owned by one Alfred Kolb. While still an undergraduate student at the Darmstadt Engineering College, Klob had laid out the designs for the world's first such grinder and, with a suitable family background to support him - his father owned an engineering works - upon completing his studies in 1936, his early ideas were turned into a prototype, the PFS-1. Interviewed years later he said, "Damals ahnte ich noch nicht, dass diese Maschine nicht nur mein Lebenswerk, sondern auch meine Berufung werden sollte." (I had at the time no idea that this machine was to become not only my life's work, but also its vocation).
With the first machine built and put into use, its capabilities were immediately realised with tool and jig work completed not only more quickly but to improved precision as well. Based upon this success - and with experience gained in its application to a range of jobs - a second prototype, the PFS-2, was built. This model had the workpiece arranged to the right-hand side, close to the projection desk, bringing it within immediate reach of, and also easily visible by, the operator. All subsequent versions of the PeTeWe were to follow this basic layout and, when the grinder was first shown in public at the Technical Spring Fair in Leipzig in 1938, it aroused significant interest. Further developed as the PFS-3, it was then put into series production from 1939 onwards with many built before the end of WW2 in 1945.
At the end of the war, in May 1945, the original works in Aschaffenburg received a 'dismantling order' from the occupying Allied Command and so production was forced to end. Fortunately, a subsidiary factory had been established in 1943 in Wertheim, a town in south-western Germany, in the state of Baden-Württemberg, and it was from there that manufacture of the machines managed to continue.
In the late 1940s, the PFS-3 was to be supplemented - but not replaced - by a projection 'circular-form' grinding machine the PFS-3d-r, a model steadily developed during the following decade and then joined by the PFS-4u. This latter model, based on the mechanical system used on all previous types and incorporated all the experience gained by the Company over several decades.
The PFS-4U could perform the following operations:
Flat form grinding for such as form gauges and counter gauges, form plates, forming dies, blanking and draw dies, etc.
Flat from relief grinding e.g. straight-relief ground forming tools, etc.
Axial circular form grinding for work on cams, blanking dies, draw dies, etc.
Radial circular form grinding for circular forming tools, profiling rollers and printing rollers, etc. The machine, with dimensions of 240 cm x 185 cm x 195 cm and with a weight of approximately 4500 kg,  is illustrated and explained in detail in the pages that follow.