Starrett 51009 Micrometer Calibration Standard 21 in

Product Description

The STARRETT 51009 is a spherical end micrometer calibration standard designed for use with outside micrometers requiring a precision reference gauge. At 21 inches in length and calibrated to an accuracy of 0.00025 inch, this standard provides a reliable traceable reference for verifying or setting micrometer readings across a wide measurement range. The unit ships calibrated and includes a heat insulating handle, which prevents thermal expansion errors caused by hand contact during use. Calibration technicians, metrology lab personnel, and precision machinists depend on this type of standard to maintain measurement integrity across their tooling inventory.

This calibration standard is suited for metrology labs, quality control departments, and precision machine shops where micrometer accuracy must be verified at regular intervals or following tool repair. The 21-inch length accommodates larger-range outside micrometers common in aerospace, heavy manufacturing, and industrial production environments. The included heat insulating handle is especially important in shop-floor applications where temperature stability directly affects measurement accuracy.

Key Features

• Calibrated to 0.00025 inch accuracy for reliable micrometer verification
• 21-inch length accommodates large-range outside micrometer sets
• Spherical ends provide consistent, repeatable contact geometry
• Ships calibrated from the manufacturer
• Includes heat insulating handle to minimize thermal expansion during handling

Compatibility

Designed for use with outside micrometers requiring a precision spherical-end calibration reference standard.

Installation Notes

Calibration standards should be handled by qualified metrology or QC personnel following established gauge calibration procedures. Always use the included heat insulating handle to prevent body heat from affecting the standard length during verification. Store the standard in its case away from direct sunlight and temperature extremes when not in use. Follow your facility's gauge calibration interval schedule and applicable standards such as ASME B89 when documenting calibration results.