Spi 10-757-3 Mechanical Hole Micrometer 8-9 in

Product Description

The SPI 10-757-3 is a mechanical inside hole micrometer designed to measure bore diameters from 8 to 9 inches with high precision. It delivers a graduation of 0.0002 inches and an accuracy of 0.0008 inches, making it suitable for close-tolerance bore inspection work. The three-contact-point design with solid carbide measuring anvils ensures consistent, repeatable readings across the full measurement range. A ratchet stop thimble provides controlled feel and prevents over-tightening during measurement. This instrument is used by machinists, metrology technicians, and quality control professionals in manufacturing and industrial environments.

This hole micrometer is suited for precision bore measurement applications in machine shops, maintenance facilities, and inspection departments. Its self-aligning and self-centering contact system reduces operator error and speeds up setup when gauging large-diameter bores. The 5.51-inch gauge depth allows reach into deep bore applications that shorter instruments cannot access. No extension rods are included, and the measurement range is fixed at 8 to 9 inches.

Key Features

• Measurement range: 8 to 9 inches with 0.0002-inch graduation
• Accuracy rated at 0.0008 inches across the full range
• Solid carbide measuring anvils for extended wear resistance
• Three-contact-point design with self-aligning and self-centering action
• Ratchet stop thimble for consistent measuring force
• 5.51-inch gauge depth for access into deep bore cavities

Compatibility

Designed as a direct-use precision measuring instrument for bore diameters from 8 to 9 inches; no additional extension rods or setting rings are included with this unit.

Installation Notes

This instrument is used by machinists and metrology technicians and requires no installation. Before use, verify the micrometer reads correctly against a known reference standard or master ring gauge. Keep the measuring faces clean and free of debris to maintain accuracy. Store in the provided case away from temperature extremes to prevent thermal expansion errors.