Measuring Instrument INSIZE 3-Point Analog Bore Gauge 50-100 mm

The INSIZE 3-Point Analog Bore Gauge 50-100 mm is a mechanical measuring instrument designed for quick comparative checks of internal diameters. It measures bores, cylinders and bearings with three contact points that determine the size and concentricity of the internal surface. The analog dial indicator provides a direct visual reading of deviations from a preset reference, making it suitable for workshop use and routine inspection tasks where fast, repeatable measurements of internal diameters between 50 and 100 mm are required.

Advantages

The three-contact measuring head ensures stable alignment inside the bore and reliable centring for repeatable readings. The analog dial offers immediate visualization of deviations without the need for batteries or electronic setup, and the mechanical construction yields robust performance in workshop environments. The measuring range covers common medium-size bores, allowing one instrument to serve multiple inspection and machining checks.

Suitable for

• Comparative measurement of internal diameters in bores and cylinders
• Inspection of bearing housings and sleeves
• Verification of machining operations and quality control in workshops
• Maintenance checks where quick in-place measurements are needed

Key specifications

• Measuring range: 50–100 mm
• Measuring principle: three-point contact
• Indicator type: analog dial reading
• Application: internal diameter and runout checks
• Construction: mechanical, non-electronic design suitable for workshop use

How to use

Select the appropriate preset or master gauge and set the dial indicator to zero or the known reference. Insert the bore gauge into the hole so the three contact points engage the internal surface, ensuring the gauge is perpendicular to the axis of the bore. Rock the gauge gently to find the maximum reading and read the deviation on the dial indicator. Compare the reading to the reference to determine the actual internal diameter or to assess runout and out-of-round conditions.

Usage recommendations

Handle the instrument by the body and avoid striking the contact points. Keep the gauge and dial indicator clean and protected from chips and coolant. Use a calibrated reference standard when setting the instrument for critical measurements, and allow the workpiece and gauge to reach the same temperature for best accuracy.