Measuring tool INSIZE SREDNICOWKA 3-point analog 16–20 mm

INSIZE SREDNICOWKA 3-point analog 16–20 mm is a compact mechanical measuring tool designed for rapid external diameter checks of small cylindrical parts. The instrument employs three equally spaced contact points that automatically center on shafts, pins and round workpieces within the 16–20 mm range and transfer the result to an analog dial for immediate reading. Built for workshop and quality-control use, this 3-point caliper offers a simple, purely mechanical solution when quick manual verification of diameter is required without digital electronics.

Advantages

The three-point centering system ensures stable contact with cylindrical surfaces and reduces eccentricity errors compared with two-point measures. The analog dial provides continuous, readable movement that is easy to interpret for routine checks. Its compact size and mechanical operation make the instrument robust, battery-free and suitable for use in environments where simple, reliable dimensional checks are preferred. The device is appropriate for repeated spot checks and basic quality control workflows.

Suitable for

• Measuring external diameters of shafts, pins and small round parts (16–20 mm)
• Quick manual inspection on the workshop floor
• Incoming goods control and simple quality-assurance tasks
• Use in assembly stations for pass/fail diameter verification

Key specifications

• Measurement range: 16–20 mm
• Measuring principle: three-point contact, mechanical centering
• Display type: analog dial indicator
• Contact points: three fixed probes for external diameter measurement
• Construction: compact, mechanical body designed for workshop use

How to use

Place the instrument around the cylindrical part so the three contact points touch the surface. Gently close the contacts until the probes are seated evenly around the circumference and the dial has stabilized. Read the diameter value from the analog dial; if required, repeat the measurement at different axial positions to confirm consistency. Keep hands steady during reading to avoid parallax errors and ensure reliable manual verification.

Usage recommendations

Before each measuring session, check that contact points are clean and free of burrs or debris; ensure the dial returns to zero when fully opened. For improved repeatability, measure at several circumferential positions and average results if necessary. Store the instrument in a protective case when not in use to preserve alignment and prevent damage to the contact points.