Precision Miniature Ball Grades & Tolerances
| GRADES & TOLERANCES – INCHES | |||||||
| AMBA Grade |
DIN Grade |
Deviation from Spherical Form |
Lot Diameter Variation |
Allowable Ball Gauge Variation |
Nominal Ball Diameter Tolerance |
Marking Increments |
*Max. Surface Roughness in Micro-inches "Ra" |
| 3 | – | .000003 | ±.000003 | ±.00003 | – | .000010 | .5 |
| 5 | – | .000005 | ±.000005 | ±.00005 | – | .000010 | .8 |
| 10 | I | .000010 | ±.000010 | ±.00005 | – | .000010 | 1.0 |
| 25 | II | .000025 | ±.000025 | ±.00010 | – | .000010 | 2.0 |
| 50 | III | .000050 | ±.000050 | – | ±.0002 | .000050 | 3.0 |
| 100 | IV | .0001 | ±.0001 | – | ±.0005 | – | 5.0 |
| 200 | – | .0002 | ±.0002 | – | ±.0010 | – | 8.0 |
| 500 | – | .0005 | ±.0005 | – | ±.0025 | – | – |
| 1000 | V | .0010 | ±.0010 | – | ±.0050 | – | – |
*Maximum surface roughness is an arithmetic average.
| GRADES & TOLERANCES – MILLIMETER | |||||||
| DIN Grade |
AMBA Grade |
Deviation from Spherical Form |
Lot Diameter Variation |
Allowable Ball Gauge Variation |
Nominal Ball Diameter Tolerance |
Marking Increments |
*Max. surface roughness in micro-meters "Ra" |
| – | 3 | .00008 | ±.00008 | ±.0008 | – | .00025 | 0.012 |
| – | 5 | .00013 | ±.00013 | ±.0013 | – | .00025 | 0.020 |
| I | 10 | .00025 | ±.00025 | ±.0013 | – | .00025 | 0.025 |
| II | 25 | .0006 | ±.0006 | ±.0025 | – | .00025 | 0.051 |
| III | 50 | .0012 | ±.0012 | – | ±.0051 | .00127 | 0.076 |
| IV | 100 | .0025 | ±.0025 | – | ±.0381 | – | 0.127 |
| – | 200 | .0050 | ±.0050 | – | ±.0250 | – | 0.203 |
| – | 500 | .0125 | ±.0125 | – | ±.0635 | – | – |
| V | 1000 | .0250 | ±.0250 | – | ±.1270 | – | – |
*Maximum surface roughness is an arithmetic average.