With this system the collet remains stationary coupled to the spindle clamping nut while the rear tapered cylinder advances for tightening.The collet is changed quickly by simply loosening the front clamping nut. The collet closes parallel to the bar without interfering on its position. Main uses Applied to the lathe counter-spindle, tighten the piece without loading the spindle axis and do not trigger the alarm of the C.N.C. Suitable for bar and secondary machining,with excellent tightening repeatability. Available in the following models: SMS 45 – bar passage ø 45 mm SMS 65 – bar passage ø 65 mm SMS 80 – bar passage  ø 80 mm SMS 95 – bar passage ø 95 mm SMS 140 – bar passage ø 140 mm All models are COMPATIBLE with DIN 6343 collets.


• Minimum clearance • Quick change clamping nut • Bar clamping with stationary collet • Does not mark the surface of the piece • Fewer machine downtimes • Machining tolerance lower than DIN tables • Range of machining: -1.0 mm • Clamping of raw pieces (rolled, forged, castings).


Secondary machining A seat for a retainer with adjustable tip to use in secondary machining has been realised inside the collet sleeve. Quick change clamping nut Just loosen the clamping nut to remove it and change the collet. Bar machining A seat for a bar orientation bush has been realised inside the collet sleeve. Via the automatic loader, the bush allows the orientation with the closing collet, in the loading phase. Ideal for hexagonal, square or profile bars.



SMS clamping collets are made up from metal inserts, units of vulcanised rubber. This allows the collet to close radially in a perfect manner, blocking the piece along the entire length of the hole and eliminates the intrusion of shavings to pass inside the spindle. Applied to the lathe main spindle it is suitable for bar machining. Moreover, the construction flexibility of the system allows easy specific solutions (drawn bars, rectified items, rolled items, pipes). 03_Unilock_COLLET CHUCK_DEAD-LENGTH_COLLET SYSTEM-3


Tapered coupling closure This feature allows each individual sector if the collet to close radially, thus clamping the piece along the entire length of the hole and developing a clamping force from 5 to 10 times greater with respect to “traditional mono-cone” collets, which only close on the front edge.They replace the double cone collets. Bar clamping with stationary collet The Unilock collet closes parallel to the bar axis without interfering in movement of the same. In this way, it does not load the lathe counterspindle axis. Excellent elasticity Thanks to its high elasticity, the Unilock collet is adaptable to the imperfections of the bar to be clamped. Suitable for machining rolled, forged and cast elements. Reduction of the vibrations The strong clamping force of the Unilock collet greatly reduces vibrations and resonances. Does not mark the surface of the piece During the clamping phase, thanks to the use of a fixed collet closing system (as jaws of self-centering) the bar or the piece is not scratched or marked by the collet. Fewer machine downtimes  The Unilock collets do not have cuts. This feature makes it almost impossible for dirt to form inside the spindle.