Starrett 51003 Micrometer Calibration Standard 18 in

Product Description

The STARRETT 51003 is a spherical end micrometer calibration standard designed to verify and maintain the accuracy of outside micrometers. At 18 inches in length and calibrated to an accuracy of 0.00025 inches, this standard is built for precision measurement environments where traceability and repeatability are critical. The unit ships calibrated and includes a heat insulating handle to prevent thermal expansion errors caused by hand contact during use. Machinists, quality control technicians, and calibration lab professionals rely on this type of standard to confirm that measurement tools are performing within specification.

This calibration standard is used in metrology labs, machine shops, and manufacturing quality assurance settings where micrometer accuracy must be periodically confirmed. The 18-inch length accommodates larger-range outside micrometers. The spherical end geometry ensures consistent contact point engagement across micrometer anvil and spindle faces. It is suited for both initial tool qualification and routine in-service verification programs.

Key Features

• Calibrated to an accuracy of 0.00025 inches for reliable measurement verification
• 18-inch maximum length accommodates large-range outside micrometers
• Spherical ends provide consistent, repeatable contact with micrometer faces
• Includes heat insulating handle to minimize thermal expansion during handling
• Ships pre-calibrated for immediate use in verification workflows

Compatibility

Designed for use with outside micrometers requiring an 18-inch calibration standard. No specific compatible model numbers were provided in the product data.

Installation Notes

Calibration standards should be handled by qualified metrology or quality assurance personnel. Always allow the standard and the micrometer being checked to stabilize to the same ambient temperature before use to avoid thermal measurement error. Use the included heat insulating handle to minimize heat transfer from hands to the standard during the calibration process. Store the standard in its protective case when not in use to prevent surface damage that could affect accuracy.