Framing square

Product overview
Innovacera’s ultra-precision ceramic master square is a metrology reference designed to establish straight and 90° reference planes for inspection and alignment tasks. It is intended for assessing straightness of motion axes, squareness between axes, and perpendicularity between adjacent workpiece surfaces.

Construction and materials
Made from high-purity alumina (Al2O3) or silicon carbide (SiC), the master square is precision-machined, ground and geometrically inspected to achieve micron-level straightness and squareness on its measurement faces. The four-window lightweight frame reduces self-weight deformation while retaining high structural rigidity, facilitating installation, reversal and comparative measurements in multiple orientations.

Usage
The ceramic master square is used with displacement sensors (electronic comparator, dial indicator, inductive probe, air gauge, CMM probe) and does not display measurements itself. Typical applications include installation, adjustment and periodic geometric accuracy checks of precision machine tools, coordinate measuring machines, semiconductor equipment and automated inspection platforms.

Product features

• Micron-level geometric accuracy
• High-rigidity, lightweight four-window frame
• Excellent wear resistance
• Corrosion- and rust-resistant
• Non-magnetic design
• Good dimensional stability
• Custom manufacturing available

Specifications:
Model | Size (L × H × W) | Straightness | Squareness | Weight
INV202050-SG | 200 × 200 × 50 mm | < 1.5 µm | < 1.5 µm | 3.5 kg
INV353550-SG | 350 × 350 × 50 mm | < 1.5 µm | < 1.5 µm | 8.1 kg
INV404050-SG | 400 × 400 × 50 mm | < 1.5 µm | < 1.5 µm | 11 kg
INV454550-SG | 450 × 450 × 50 mm | < 2 µm | < 2 µm | 12.5 kg
INV505055-SG | 500 × 500 × 55 mm | < 2 µm | < 2 µm | —
Custom Size | Up to 1000 × 400 × 50 mm | < 2 µm | < 2 µm | By design

Main applications

• Geometric accuracy inspection for precision machine tools
• Coordinate measuring machines and metrology equipment
• Semiconductor and precision automation equipment
• Inspection of workpieces and precision fixtures

Typical measurement methods
Comparative measurement
Secure the ceramic master square on a precision surface plate and move the probe along a measurement face. Record indicator variations at different positions to evaluate axis straightness, surface straightness and angular deviation.

Reversal measurement
Rotate or reverse the master square (180° or change mounting orientation) to separate the square’s inherent error from the equipment motion error, improving reliability of the geometric error analysis.

Multi-axis squareness inspection
Use one measuring face as the datum and an adjacent face to establish a 90° reference for checking squareness between two motion axes.

Technical characteristics / specifications:

• Materials: High-purity alumina (Al2O3) or silicon carbide (SiC)
• Geometric accuracy: Micron-level straightness and squareness (model dependent: typically <1.5 µm to <2 µm)
• Standard sizes: 200×200×50 mm to 500×500×55 mm; custom up to 1000×400×50 mm
• Lightweight four-window frame to reduce self-weight deformation
• High structural rigidity and wear resistance
• Non-magnetic, corrosion-resistant, rust-free
• Intended use with displacement sensors (electronic comparator, dial indicator, inductive probe, air gauge, CMM probe)
• Typical model codes: INV202050-SG, INV353550-SG, INV404050-SG, INV454550-SG, INV505055-SG