Spi 22-308-1 Dial Drop Indicator 0.001 in Graduation

Product Description

The SPI 22-308-1 is a dial drop indicator designed for precise linear measurement in machining, tooling, and inspection applications. It features a 0.001-inch graduation with a 0-100 dial reading scale and a total measurement range of 0.5 inches. The 2.2-inch white dial face provides clear readability, and a built-in revolution counter tracks full spindle cycles for accurate cumulative readings. Accuracy is rated at 0.002 inches, and the unit ships with a NIST Traceability Certification. This indicator is a standard tool for machinists, quality control technicians, and precision measurement professionals.

The 22-308-1 is suited for use in machine shops, manufacturing inspection stations, and toolroom environments. It mounts via a lug-style back and accepts standard accessories through its 3/8-inch stem diameter, allowing integration with magnetic bases, indicator holders, and surface plate setups. The 0.1-inch range per revolution makes it well-suited for fine runout checks, surface flatness verification, and fixture alignment tasks requiring tight tolerances.

Key Features

• 0.001-inch dial graduation for high-resolution linear measurement
• 0-100 dial reading scale with 0.5-inch total measurement range
• Built-in revolution counter for tracking full spindle cycles
• 2.2-inch white dial face for easy reading at a distance
• Lug back mounting with 3/8-inch stem diameter for universal positioning
• Includes NIST Traceability Certification meeting US Federal Specifications

Compatibility

Designed as a standard AGD Group 2 dial drop indicator compatible with conventional lug-back indicator holders, magnetic base arms, and 3/8-inch stem-diameter mounting accessories used in general precision measurement setups.

Installation Notes

Installation and use of this indicator should be performed by qualified machinists or metrology technicians familiar with precision measurement equipment. Mount the indicator securely in a compatible holder using the lug back before applying any measuring force to the spindle. Verify the mounting assembly is rigid and free of play before taking readings. Do not exceed the rated measuring force, as excess load can affect accuracy and damage the mechanism.