Precision Ball Grades

A.F.B.M.A Ball Grades and Tolerances

Grade

Sphericity

Basic Diameter Tolerance

 3

.000003″

  +/- .00003″

5

 .000005″

  +/- .00005″

 10

.000010″

 +/- .0001″

 25

 .000025″

  +/- .0001″

 50

.000050″

  +/- .0002″

 100

.0001″

  +/- .0005″

 200

.0002″

  +/- .0010″

 500

.0005″

  +/- .002″

 1000

 .001″

  +/-.005″

 

Grade

The guaranteed sphericity expressed in millionths of an inch. For example, a grade 25 ball is spherically accurate within 25 millionths of an inch.

Sphericity

The difference between the largest diameter and the smallest diameter on a single ball.

Basic Diameter Tolerance

The maximum allowable deviation from the basic diameter.

 

 

Plastic Grades are Different:

 

Plastic Grades and Tolerances
Grade Tolerance Sphericity
1 +/- .001″ .0005″
2 +/- .002″

.001″
3 +/- .005″ .005″

The information on this web site is intended for guidance only. Since we gathered technical data from various technical sources, the actual mechanical and physical properties will vary from one lot of material to the next. Therefore, we accept no liability for deficiencies or damages arising from the use of this data, and customers should determine the suitability of a material or product by conducting practical tests under realistic conditions.