Starrett 66428 Ball Anvil Micrometer 0 to 1 Inch

Product Description

The STARRETT 66428 is a mechanical ball anvil micrometer designed for precision outside measurement from 0 to 1 inch. The carbide-faced ball anvil and flat carbide spindle provide durable contact surfaces suited for measuring curved or irregular workpiece geometries where a standard flat anvil would not seat correctly. Graduation is 0.001 inch, allowing direct readings without interpolation. The satin chrome finish reduces glare under shop lighting. A plain thimble and plain lock nut are included along with a wrench. This tool is used by machinists, tool-and-die tradespeople, and precision measurement technicians working in manufacturing and fabrication environments.

The 66428 is applied in situations where a conventional flat anvil micrometer cannot make accurate contact — such as measuring wall thickness on tubing, seating depth on curved surfaces, or diameter at specific points on contoured parts. The ball anvil design concentrates the contact point, ensuring repeatable seating. The mechanical operation requires no battery and functions in environments where electronic instruments may be impractical. Typical users include machine shop technicians, quality control inspectors, and maintenance tradespeople performing close-tolerance work.

Key Features

• Ball anvil with carbide face for reliable contact on curved and irregular surfaces
• Flat carbide spindle for consistent wear resistance and measurement accuracy
• 0.001 inch graduation for direct, precise readings
• Satin chrome finish minimizes glare in shop and inspection environments
• Plain thimble with plain lock nut — no ratchet mechanism to maintain
• Includes lock nut and wrench for field adjustment

Compatibility

Designed as a standard 0 to 1 inch range mechanical outside micrometer for general precision measurement applications in machining, fabrication, and quality control.

Installation Notes

Ball anvil micrometers are hand tools requiring no installation. Before use, clean the anvil and spindle faces with a lint-free cloth and verify zero calibration using a standard reference. Store the micrometer with the spindle backed off slightly from the anvil to prevent spring fatigue. Do not use power tools or impact methods to advance the thimble.