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The ROVI Mini Master is essentially a modified 1″ ROVI Expanding Collet, which has been machined down and ground to very close tolerances. After assembling the Mini Master with the Sleeve and Rod Assembly, it becomes a carrier for the Mini Collet, and expands from the inside. This permits full use of the front part of the Mini Collet allowing it to be machined to very small diameters without interference of an expanding screw.

CART mini collet


  1. Clean taper of Mini Master and inside taper of Sleeve and drive Mini Master securely into Sleeve.
  2. Insert Rod Assembly through rear of Sleeve into Mini Master.
  3. Insert Expanding Screw through front of Mini Master into Rod Assembly and bottom screw into Threaded Rod. Hand tighten only until Step 5.
  4. Loosen Lock Nut and adjust Collet Nut so Rod Assembly will travel approximately 1/8″ to 3/16″
  5. Tighten Lock Nut and tighten Expanding Screw securely so neither will loosen itself. Be sure to tighten Lock Nut first and then the Expanding Screw.
  6. Slide Mini Collet over Mini Master. Line up slots on Mini Collet with those of Mini Master and lock tight with Locking Collar.
  7. Insert assembled unit into machine. Adjust Collet closer until Collet expands slightly and machine to desired size. Chucking length ordinarily should not be turned back more than 11/2 times its diameter.
  8. To disassemble, remove Locking Collar, slide Mini Collet off Mini Master. Loosen Expanding Screw entirely, rear of Rod Assembly will then come out. To separate Sleeve from Mini Master insert snug fitting metal rod into rear of Sleeve and give a good smack with a hard hammer. Or, we suggest using the ROVI Collet Separator. Mini Master and Sleeve should separate readily.
  9. We suggest that use use the Rovi Turning Ring when machining the collet to your desired diameter. This encapsulates the collet so that it will not over expand.