Spi 21-233-2 Cupped Ball Contact Point Dial Indicator

Product Description

The SPI 21-233-2 is a cupped ball contact point designed for use with dial indicators in precision measurement applications. Machined from steel, this contact point threads onto standard dial indicator stems using a 4-48 thread. It measures 0.118 inches in diameter and has a contact point length of 0.28 inches, conforming to AGD Group 1 industry standards. The cupped ball tip style provides stable, repeatable contact on rounded or irregular workpiece surfaces, making it a reliable choice for metrology professionals, machinists, and quality control technicians who require consistent gauge readings.

This contact point is used in shop-floor and inspection environments where dial indicators are employed to measure runout, surface variation, concentricity, or part deflection. It is suited for both manual gauging setups and fixture-mounted indicator applications. The AGD Group 1 designation confirms dimensional compatibility with a wide range of standard dial indicators used in industrial and precision measurement settings.

Key Features

• Cupped ball contact point style for stable contact on curved or uneven surfaces
• Steel construction for durability in production and inspection environments
• 4-48 thread size for compatibility with AGD Group 1 dial indicators
• 0.118 inches contact diameter and 0.28 inches contact point length
• Conforms to AGD Group 1 industry designation

Compatibility

Designed for use with dial indicators accepting a 4-48 threaded contact point, conforming to AGD Group 1 specifications.

Installation Notes

Contact point replacement is typically performed by metrology technicians or machinists. Thread the contact point onto the dial indicator stem by hand, then snug it carefully to avoid cross-threading or over-torquing the fine 4-48 threads. Ensure the indicator is removed from any active measurement fixture before replacing the contact point. Inspect threads on both the contact point and indicator stem for damage before installation.