Starrett 12305 Dial Test Indicator 0.03 in Horizontal

Product Description

The STARRETT 12305 is a horizontal-style dial test indicator designed for precision measurement in machining, inspection, and metrology applications. Built on the Series 3909 platform, it delivers a maximum measurement range of 0.03 inches with a fine graduation of 0.0005 inches per division, enabling accurate runout, flatness, and alignment checks. The jeweled movement and precision gear-driven design reduce friction and wear for repeatable readings over the service life of the tool. The narrow body and dovetail mount make it straightforward to position in tight setups. A satin chrome finish provides durability and reduces glare during use. Licensed machinists, toolroom technicians, and quality-control inspectors are the primary users of this indicator.

This indicator is suited for use on machine tools, surface plates, CMM setups, and inspection fixtures in both production and job-shop environments. The 0-15-0 bidirectional dial reading allows the technician to detect deviation in either direction without repositioning the indicator. The automatic contact-point reversal feature supports applications where the probe must work from multiple angles without manual adjustment. The high-contrast white dial with 1.25-inch diameter face keeps graduation marks legible under shop lighting conditions.

Key Features

• 0.03 inch maximum measurement range with 0.0005 inch graduation for fine-resolution readings
• Jeweled bearing movement with precision gear-driven design for long-term accuracy and repeatability
• Horizontal indicator style with dovetail mount for compatibility with standard indicator holders and arms
• Contact point reverses automatically, supporting measurements from multiple probe orientations
• Narrow body design allows access in confined setups and close-tolerance fixturing
• Includes two contact points, two dovetail clamps, swivel post holder, tool post holder, contact wrench, and carrying case

Compatibility

Designed for use with standard dovetail-style indicator holders, swivel post holders, and tool post holders as supplied; fits typical dovetail mounting arrangements used with horizontal dial test indicators in the Series 3909 family.

Installation Notes

Installation is performed by qualified machinists or metrology technicians using the included dovetail clamps and holder hardware. Ensure the machine or workpiece is powered down and secured before mounting the indicator. Avoid overtightening the dovetail clamp, which can distort the indicator body and affect reading accuracy. This tool is a precision instrument and should be stored in the provided case when not in use to protect the jeweled movement from shock and contamination.