Spi 17-918-4 Mechanical Hub Micrometer 1-2 Inch

Product Description

The SPI 17-918-4 is a mechanical hub micrometer designed for precise outside diameter and hub measurements in the 1 to 2 inch range. It delivers 0.0001 inch graduation and 0.0002 inch accuracy, making it suitable for close-tolerance work in machining, tooling, and quality inspection applications. The rotating spindle design and ratchet thimble allow for consistent measuring force, reducing operator-to-operator variation. Both the spindle and anvil are carbide-tipped for long-term wear resistance. This tool is factory calibrated and ships with a short-form certificate of calibration, a case, and standards documentation.

The SPI 17-918-4 is used in precision measurement workflows across manufacturing, machine shops, maintenance facilities, and inspection departments. It is well suited for measuring shaft hubs, bores, and outside diameters on turned or ground parts where a standard outside micrometer may not provide adequate contact geometry. Technicians and machinists performing dimensional inspection, first-article checks, or in-process quality control will find this micrometer appropriate for bench and floor use alike.

Key Features

• 1 to 2 inch measuring range with 0.0001 inch graduation
• 0.0002 inch accuracy for close-tolerance inspection work
• Ratchet thimble ensures consistent, repeatable measuring force
• Rotating spindle design for hub and shoulder measurement applications
• Carbide anvil and carbide spindle for extended wear life
• Ships calibrated with a short-form certificate of calibration, case, and standards

Compatibility

Designed as a direct-use precision measuring instrument for any application requiring hub or outside diameter measurement in the 1 to 2 inch range. No system integration or replacement compatibility is specified for this tool.

Installation Notes

This micrometer requires no installation. Handle with care to avoid dropping, which can affect calibration and spindle alignment. Store in the included case when not in use and keep out of contact with coolants, oils, or abrasive debris that can damage the measuring faces. Re-calibration should be performed periodically per your facility quality plan or applicable metrology standards.