Starrett 67680 Mechanical Micrometer 6 in Ratchet Stop

Product Description

The STARRETT 67680 is a mechanical outside micrometer designed for high-precision measurement in demanding shop and field environments. It covers a measurement range up to 6 inches and delivers an accuracy of 0.000250 inches with a graduation of 0.0003 inches. The ratchet stop thimble provides consistent, repeatable gauging pressure so readings remain accurate regardless of operator technique. Measuring faces are solid carbide for long-term wear resistance. This tool is used by machinists, toolmakers, and precision measurement technicians who require dependable dimensional verification on critical workpieces.

The STARRETT 67680 is suited for precision measurement tasks in manufacturing, tool-and-die, quality control, and maintenance environments. With a 3-contact-point design and a gage depth of 4.5 inches, it handles larger or irregular workpieces where standard two-point micrometers fall short. A setting ring with a 5-inch diameter is included for calibration and zeroing. This micrometer is appropriate for both bench use and in-process inspection in residential shop settings as well as light industrial applications.

Key Features

• Measurement range up to 6 inches (125.00 mm minimum measurement)
• Accuracy of 0.000250 inches for high-precision dimensional work
• Graduation of 0.0003 inches for fine resolution readings
• Ratchet stop thimble ensures consistent gauging pressure across operators
• Solid carbide measuring faces resist wear for extended service life
• 3-point contact design with 4.5-inch gage depth for larger workpieces

Compatibility

Designed as a standalone precision measuring instrument for general outside-diameter and flat-surface measurement applications. Includes a 5-inch setting ring, contacts, wrenches, instructions, and a storage case as packaged.

Installation Notes

This instrument requires no installation but should be calibrated using the included setting ring before first use and after any impact or extended storage. Store in the provided case to protect measuring faces and the thimble mechanism. Avoid applying excessive clamping force to the workpiece; use the ratchet stop consistently to prevent over-tightening. Cleaning the measuring faces with a lint-free cloth before use helps prevent contamination-related reading errors.