Grinding process for a knife shaft

The present invention relates to a process to grind a knife shaft (40,50) used in a machine intended for cutting sheets of materials into strips, for example sheets of paper, plastic, plates of photosensitive film or any other material having the form of thin sheets. The process consists in determining the actual differences of position of the knives (20,30) of the knife shaft (40,50) in relation to a theoretical position and then dividing these differences to cut the film strips by widths practically equal to one another and in determining the quantities of material to be eliminated by grinding for each knife. This process especially finds its principal application in the photographic industry, in particular on grinding machines for the knives of knife shafts equipping the film slitters.