NSK Micromotor — Bench Standard for Jewellery and Lapidary Detail
NSK Micromotor — Bench Standard for Jewellery and Lapidary Detail
An electric or air-driven rotary handpiece system from Japan, valued for high torque and low vibration
The NSK micromotor is a high-speed electric or air-driven rotary handpiece system manufactured by Nakanishi Inc. of Japan, widely used in jewellery making, gem setting, lapidary work, and dental and surgical practice. NSK micromotors deliver speeds from 1,000 to over 50,000 rpm with controlled torque, low vibration, and precision spindle alignment, accommodating burrs, drills, and polishing tools across a wide range of applications.
Why micromotors matter
The micromotor format separates the motor from the handpiece — the motor sits at the bench in a control unit, the handpiece is a slim, lightweight tool connected by a flexible shaft or cable. This arrangement reduces hand fatigue, places the heat-generating motor away from the operator's hand, and permits fine control over speed and torque through electronic regulation.
For jewellers, micromotors are used for stone setting (drilling seats, opening prongs), polishing internal surfaces, removing flash from castings, and detail engraving. For lapidaries, micromotors power small diamond burrs and grinding wheels for carving, fine shaping, and intricate detail. The combination of high speed and high torque distinguishes micromotors from simpler flex-shaft and rotary tools, which sacrifice one or the other.
Configurations
NSK offers electric and air-driven micromotors. Electric models — such as the popular Volvere and Surgic series — provide programmable speed control, torque limiting, and consistent operation independent of compressed-air supply. Air-driven models, including the Presto turbines, achieve much higher speeds (up to 300,000 rpm or more) but with lower torque and dependence on a clean, regulated air source. Bench operations typically use electric micromotors as the primary tool, reserving air turbines for the highest-speed detail work.
Handpieces accept a range of collets, with 3 mm and 2.35 mm being common standards for lapidary and dental burrs respectively. Adapter collets and reducer sleeves allow mixed tool inventories.
Maintenance and durability
NSK's reputation for durability rests on the quality of the spindle bearings and the precision of the speed control electronics. With routine maintenance — bearing lubrication, replacement of consumable seals, and care to avoid contamination of the spindle — handpieces last for years of professional use. The systems are not inexpensive, but the cost is justified for high-volume bench work where reliability and precision matter.