The 036.120 feed finger collet is a technical component for Cucchi automatic bar feeders, manufactured with M7X0.75 thread and 12 mm outside diameter. Its function is to grip the bar, guide it correctly and transmit the feed movement generated by the bar feeder towards the lathe. It is used on automatic lathes, CNC lathes and Swiss-type CNC machines, where feeding stability, gripping quality and correct material position in relation to the machine axis are essential for production continuity, dimensional accuracy and machining-cycle reliability.

During the machine cycle, the collet works as the connecting element between the feeder pushing system and the bar to be fed. The 12 mm outside diameter and M7X0.75 thread identify a compact component for feeding systems where available space, precision of the threaded connection and smoothness of movement are particularly important. The closing action on the material must be stable, repeatable and consistent with the bar geometry, because insufficient gripping can cause slipping, irregular feeding and loss of position, while incorrect gripping may mark the material, generate vibration or cause sticking.

In Swiss-type CNC machining, where the material is supported and machined in conditions that are highly sensitive to alignment, a correctly selected collet helps reduce form errors, surface-finish defects, transmission backlash and micro-movements during automatic feeding. The collet is not a measuring instrument, but it requires accurate dimensional and geometric checks because bar diameter, concentricity, spindle-line height, coaxiality between feeder and lathe and guide condition directly influence the precision of the complete feeding system. Correct matching between collet and bar provides smoother pushing, better repeatability and reduced machine downtime.

The TD-036.120 collet should be selected by considering the Cucchi feeder model, nominal or real bar diameter, material profile, compatibility of the M7X0.75 thread, spindle-line height, alignment between bar feeder and lathe, condition of the pusher tube, guides, bushings and backlash in the feed transmission. In automated production departments, these checks are essential to keep the process stable over repetitive batches and to limit scrap caused by feeding errors, loss of grip or irregular dragging. A worn collet or a collet not consistent with the bar profile may cause noise, vibration, discontinuous feeding, positioning errors and quality problems on the machined part.

Feed finger collets can be supplied for round, hexagonal or square bars. For profiled bars, grinding is carried out according to the corner dimension rather than a generic diameter, so that the gripping surface matches the real geometry of the material. This dedicated machining is important to prevent irregular contact, loss of centring, vibration and localised wear on the contact surfaces. For hexagonal or square profiles, correct evaluation of the corner dimension allows the collet to distribute the grip more effectively and keep the material stable during feeding, stopping and restarting phases of the bar feeder.

From an operational and maintenance point of view, the collet should be checked periodically for thread cleanliness, integrity of the gripping surfaces, absence of burrs, abnormal elastic deformation, irregular contact marks and loss of concentricity. It is also advisable to check axial settings, feeder height, alignment with the spindle, pusher tube, bushings and guides, because feeding precision depends on the interaction of all these elements and not only on the individual component. The TD-036.120 feed finger collet is suitable for machine shops, bar turning companies, CNC departments, maintenance specialists, machine builders, laboratory technicians, process engineers and quality control managers. Tadaah offers this component with attention to technical compatibility and application support, helping select the correct collet according to the installed feeder, required diameter, bar geometry and real working conditions.