Starrett 53070 Small Hole Gage 0.125 to 0.2 Inch Full Ball

Product Description

The STARRETT 53070 is a small hole gage designed to measure the internal diameter of small bores, holes, and slots where standard inside micrometers or calipers cannot reach. The tool spans a measurement range of 0.125 to 0.2 inches and features a full ball contact style that transfers a precise diameter reading to an outside micrometer for final measurement. Overall length is 2.875 inches, making it compact enough for tight access in production, maintenance, and inspection work. Machinists, tool-and-die workers, and precision mechanics rely on this type of gage to verify bore tolerances during fitting and quality control operations.

The STARRETT 53070 is suited for measuring small holes in machined components, valve bodies, bearing bores, bushings, and similar precision parts encountered in industrial maintenance and manufacturing environments. Its compact size allows access to shallow and restricted bore openings that larger measuring tools cannot contact cleanly. The full ball design provides consistent, repeatable contact geometry across the measurement range, supporting accurate bore-to-mic transfer measurements on the bench or at the machine.

Key Features

• Measurement range of 0.125 to 0.2 inches covers small bore applications
• Full ball contact style provides uniform contact for reliable diameter transfer
• 2.875 inch overall length allows access to shallow and restricted bore locations
• Lightweight at 0.016 pounds for comfortable single-hand use during inspection
• Designed for use with an outside micrometer to obtain final bore reading

Compatibility

Designed as a standard small hole gage for use with outside micrometers covering the 0.125 to 0.2 inch measurement range in general precision measurement and inspection applications.

Installation Notes

Small hole gages require no installation and are hand-operated measuring tools. Expand the ball gently inside the bore until light drag is felt, then lock the setting and transfer to an outside micrometer for the final reading. Avoid over-expanding the ball beyond the rated range, as this can damage the tool or distort the measurement. Clean the bore and gage contact surfaces before use to ensure accurate results.