Spi 20-984-1 Ball Contact Point Dial Indicator

Product Description

The SPI 20-984-1 is a ball-style contact point designed for use with dial indicators in precision measurement applications. Machined from chrome alloy steel, this contact point measures 0.75 inches in length and features a 3/8 inch diameter ball tip that provides consistent, repeatable surface contact. It threads directly onto compatible dial indicators using a 4-48 thread. This type of contact point is a standard consumable in metrology toolkits used by machinists, quality control technicians, and tool room professionals who require accurate dimensional measurement across a range of workpiece geometries.

The 20-984-1 is suited for use in machine shops, inspection departments, and production environments where dial indicators are regularly deployed for setup, runout checks, surface deviation, and part inspection. The ball contact geometry is particularly useful when measuring curved, contoured, or irregular surfaces where a flat or pointed tip would produce inconsistent readings. It conforms to AGD Group 1 industry designation, making it compatible with standard AGD Group 1 dial indicator configurations.

Key Features

• Ball contact style for consistent surface contact on curved and irregular workpieces
• Chrome alloy steel construction for durability and wear resistance
• 0.75 inch contact point length for standard reach applications
• 3/8 inch ball diameter provides a broad, stable contact footprint
• 4-48 threaded shank for secure attachment to compatible dial indicators
• Meets AGD Group 1 industry designation

Compatibility

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

Installation Notes

Installation is performed by hand-threading the contact point onto the dial indicator stem using the 4-48 thread. Avoid over-tightening, which can damage the threads on the indicator spindle. Ensure the indicator is zeroed and re-calibrated after replacing any contact point, as tip geometry changes can affect measurement baselines. Handle chrome alloy steel contact points carefully to avoid surface contamination that may affect measurement accuracy.