Spi 17-945-7 Outside Micrometer 2 Inch Ratchet Stop

Product Description

The SPI 17-945-7 is a mechanical outside micrometer designed for precise linear measurement of external dimensions. It covers a 0 to 2 inch measurement range with a graduation of 0.001 inches and an accuracy of 0.000250 inches, making it suitable for applications where tight tolerances are critical. The thimble uses a ratchet stop mechanism to apply consistent measuring pressure and reduce operator-to-operator variation. Measuring faces are solid carbide for durability and resistance to wear. A NIST traceability certification is included, supporting use in calibrated shop environments. Machinists, tool and die makers, and quality control technicians are the primary users.

This micrometer is used in machine shops, manufacturing facilities, and maintenance environments where external part dimensions must be verified to close tolerances. It is well suited for inspection of shafts, pins, fasteners, and machined workpieces up to 2 inches in diameter or thickness. The ratchet stop thimble makes it practical for production environments where repeatable measurements are taken frequently by multiple operators.

Key Features

• 0 to 2 inch measurement range with 0.001 inch graduation
• Accuracy of 0.000250 inches for tight-tolerance inspection work
• Ratchet stop thimble ensures consistent measuring pressure
• Solid carbide measuring faces resist wear over extended service life
• NIST traceability certification included for calibrated shop compliance
• Hammertone baked enamel frame finish for corrosion resistance and grip

Compatibility

Designed as a standard 0 to 2 inch range outside micrometer suitable for general-purpose external measurement tasks in machine shop, manufacturing, and quality control applications.

Installation Notes

Outside micrometers require no installation but should be stored in their protective case when not in use to protect the measuring faces and maintain calibration. Before use, clean the anvil and spindle faces with a lint-free cloth and verify the zero setting against the standard or reference gauge included or supplied separately. Periodic recalibration against a NIST-traceable standard is recommended to maintain measurement integrity. Do not over-tighten the thimble beyond the ratchet stop engagement point.