Tel: 860-571-3602  |
Tel: 860-571-3602  |

Precision Miniature Balls


Precision miniature balls are balls that are under 1/8 inch (3 mm) in diameter. They are generally made out of stainless steel or chrome, making them durable in a variety of applications. They are used where a high degree of precision is required such as the medical, automotive or electronics industry.

Miniature Ball Applications

We provide billions of precision mini balls to numerous industries such as automotive, aerospace, medical, dental, electronics, health and beauty, and other applications where small ultra-precise balls are needed, including:

  • Medical and industrial handpieces
  • Flow meters
  • Fuel controls
  • Gyros, synchros and servos
  • Motors
  • Cryogenic coolers
  • Pulmonary assist devices


Hartford offers miniature bearing balls from materials including chrome (52100) and stainless steel 440C, 300 series, 302, 304, 316.

Mini Ball Sizes

Miniature precision balls range in size from 1mm to 3mm, and from grades 10 to 50.  Grade 10 balls have a sphericity of only 10 millionths (0.00001”) of an inch and are the highest precision balls that we manufacture.


Hartford Miniature Ball Capabilities

In 2020, Hartford opened a specialized, modern state-of-the-art miniature ball facility in China. Here, we can process chrome (52100/GCr15) or 440C balls from 1mm to 3mm and from grades 10 to 50. The plant is ISO 9001 certified and can process 100 metric tons of balls per year. 

The miniature ball facility features machines for each step of mini ball processing, including cold heading, small and large flashing, heat treat (hardening) and tempering furnaces, HV hardness testers, and demagnetization equipment, among others. This Hartford facility also provides state-of-the-art ultrasonic cleaning and 100% inspection around 360 degrees of the ball surface using sophisticated vision equipment.

If you’re in the market for miniature precision balls, tell us your requirements and we’ll provide a solution. Hartford Technologies design engineers are among the most knowledgeable in the industry, and our ability to manufacture mini balls in China gives Hartford customers a substantial advantage in cost and flexibility. We produce more than one billion balls per year for high volume OEM applications and can provide fast turn-around to meet stringent delivery requirements.Request a consultation today for quick, expert applications assistance with your next miniature ball requirement.