The 218E - SH18 quick-change collet is a technical component for automatic bar feeders compatible with FMB, TRAUB, HAGENUK, IEMCA, ROBOBAR, LNS, SAMECA, MINISPRINT and MINITURBO systems, with 18 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, single-spindle lathes, multi-spindle 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 to maintain production continuity, dimensional accuracy and machining-cycle reliability.

The quick-change system is particularly useful in machine shops and production departments that process different batches, different diameters or frequent material changes. It helps reduce setup time and makes collet replacement more efficient, while still requiring attention to compatibility with the installed bar feeder and correct pusher-tube configuration. During the machine cycle, the collet works as the connecting element between the feeding device and the bar to be fed; stable gripping helps reduce slipping, irregular feeding, vibration, sticking and loss of position.

The 218E - SH18 collet should be selected by considering the bar feeder model, nominal or real bar diameter, material profile, 18 mm outside diameter, spindle-line height, alignment between bar feeder and lathe, condition of guides, bushings, pusher tube and backlash in the feed transmission. Even when the spare part is intended for several bar feeder brands, it is important to check that coupling dimensions, seat, quick-change system and machine configuration are consistent with the actual application. Correct matching between collet and bar provides smoother pushing, better feed repeatability and reduced risk of machine downtime.

Feed finger collets and quick-change 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 seat 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. A worn collet, incorrectly mounted collet or collet not consistent with the bar profile may cause noise, vibration, discontinuous feeding, positioning errors, form errors and quality problems on the machined part.

The 218E - SH18 quick-change collet is suitable for machine shops, bar turning companies, CNC departments, single-spindle and multi-spindle lathe production, maintenance specialists, machine builders, laboratory technicians, process engineers and quality control managers. It is a professional spare part used to maintain the efficiency of the feeder system and to improve continuity, reliability and precision in automatic production. 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.