Abstract: The present invention relates to a shaft 4 for planers, of the type where the peripheral surface has, formed along it, longitudinal recesses 5 each housing a working blade 1 and a prism-shaped locking or retaining bar 2, with a system for rapidly fixing said blades, comprising two series 7 and 8 of rollers housed in succession in a recess 6 parallel to and radially inside the recess 5 and a central operating member of the screw type 13, 14 and 15 able to exert an axial thrust on the toggles formed by the rollers at the two ends of the recess 6, by means of two thrust elements 11 and 12, so as to produce, on the locking bar 2, a radial thrust sufficient for fixing the blade 1. (FIG.