Spi 21-068-2 Test Indicator Ball Contact Point Ruby

Product Description

The SPI 21-068-2 is a ruby ball contact point designed for use with dial test indicators in precision measurement applications. The contact point features a 0.078 inch diameter ruby ball tip mounted on a 0.812 inch overall length stem. Ruby contact points are chosen for their hardness and wear resistance, making them well suited for high-cycle measurement tasks and contact with hardened or abrasive workpiece surfaces. This replacement contact point is installed by metrology technicians and machine shop professionals who require reliable, repeatable stylus contact during inspection routines.

This contact point is intended for use with Interapid test indicators. It is commonly used in precision inspection environments including tool and die shops, machine shops, and quality control stations where dial test indicators are used for runout, flatness, and surface deviation measurements. The small ball diameter allows access to tight features and contoured surfaces. This part is sold individually and is a direct replacement for worn or damaged stylus tips.

Key Features

• Ruby ball tip for high hardness and extended wear life in high-cycle applications
• 0.078 inch ball diameter provides precise contact on fine features and contoured surfaces
• 0.812 inch contact point length for standard reach on Interapid-style indicators
• Sold as a single unit for individual replacement without excess inventory
• UNSPSC Code 41111600 for procurement and catalog classification

Compatibility

Designed for use with Interapid test indicators as stated by the manufacturer.

Installation Notes

This contact point is installed by metrology or machine shop personnel as part of routine indicator maintenance. Before replacing the contact point, remove the indicator from the spindle or magnetic base and secure it in a stable position. Use the appropriate small wrench or contact point tool to unthread the worn tip and thread in the replacement, taking care not to overtighten or cross-thread the stem. Verify the indicator reads correctly against a known reference surface before returning it to service.