Spi 21-123-5 Ball Contact Point Carbide Tesa Indicators

Product Description

The SPI 21-123-5 is a carbide ball contact point designed for use with test indicators in precision measurement applications. The contact point features a 0.078-inch ball diameter and a total contact point length of 0.497 inches, delivering repeatable, low-wear contact on workpiece surfaces. The carbide tip material resists abrasion and deformation, maintaining dimensional accuracy over extended service cycles. This type of contact point is installed by machinists, quality control technicians, and toolroom professionals who require consistent gauge-point geometry when taking surface, bore, or runout measurements.

This contact point is suited for inspection and metrology work on precision components in both shop-floor and controlled measurement environments. It threads into compatible test indicator spindles and replaces worn or damaged stock contact points. Applications include checking part flatness, concentricity, and feature-to-feature relationships on machined parts. The small ball diameter allows access to tight features and fine surface contours where larger contact geometries would introduce error.

Key Features

• Carbide ball tip resists wear and maintains accuracy over repeated measurements
• 0.078-inch ball diameter for access to tight features and fine surface profiles
• 0.497-inch contact point length for proper reach and lever geometry on compatible indicators
• Low contact-point mass minimizes influence on sensitive indicator mechanisms
• Replacement-style fitment for field swapping during routine indicator maintenance

Compatibility

Designed for use with Tesa test indicators.

Installation Notes

Installation is performed by a machinist or metrology technician using the appropriate contact point wrench or driver to thread the point securely into the indicator spindle without over-torquing the threaded fitting. Zero the indicator after replacing the contact point to confirm proper seating and stylus deflection. Handle carbide-tipped contact points carefully to avoid chipping the ball on hard surfaces.