Master Square

Ceramic Master Square


  • 1  AA Grade 5-Face Ceramic Square
  • 1  Travel Case


  • Durable
  • Accurate
  • Comparably lightweight

P/N Size (in.) Weight (lb.)
IQL-1000-088 2x6x6 6
IQL-1000-081 2x9x12 15  
IQL-1000-090 2x14x14 22  
IQL-1000-131 3x12x12 30  
IQL-1000-082 3x12x18 33  
IQL-1000-006 3x18x24 65  
IQL-1000-089 3x18x36 80  
IQL-1000-117 3x20x20 57  
IQL-1000-127 3x24x24 80  

Made of aluminum oxide ceramic, this Master Square is comparatively lightweight and easily loads into machine tools. The advanced ceramic material is harder than granite or steel, which significantly reduces wear on the Master Square surface. The non-porous ceramic is useful in facilities with high humidity and/or high temperatures because it eliminates moisture absorption and corrosion that can cause dimensional instability.

Because the thermal expansion coefficient in ceramic is low, measurements are consistently accurate. The Master Square is finished and calibrated to required Flatness, Squareness, and Parallelism with documented traceability to NIST (National Institute of Standards and Technology).

When the Ceramic Master Square is used in conjunction with Locus® eM Measurement & Alignment Software (purchased separately), machine Squareness, Straightness, Parallelism, and Spindle Alignment can be measured by the Step by Step or On the Fly methods. Data analysis includes Least Squares Fit, End Point Fit, and No Fit.

The Electronic Gage, when used with a Master Square, provides a means of measuring the Alignment of Axes of Motion in accordance with the latest ISO 230-1 Test code for machine tools. This code requires the determination of Reference straight lines for the trajectories of the Motion axes from multiple points using the least-squares fit method.

Note: Additional Ceramic Master Squares, Ceramic Parallels, Ceramic Surface Plates, & Ceramic Straight Edges are also available in specified grades and sizes.

Granite Master Square


  • 1  AA Grade 5-Face Granite Square
  • 1  Travel Case


  • Durable
  • Accurate
  • Reasonable Price

P/N Size (in.) Weight (lb.)
IQL-1000-098 3x12x12 45
IQL-1000-099 3x14x14 61
IQL-1000-106 4x24x24 220

Granite Master Squares are ideal for inspecting the X, Y and Z axes of machine tools. This product is very stable and rigid, providing the ultimate in squareness references. This master square has 5 finished faces (1 large face and 4 edges) finished flat, square and parallel to either laboratory grade AA (.000025” per 6”). All six faces can be finished upon request.

Note: Please specify with order if lift holes or lift inserts are needed.

Note: Additional Granite Master Squares, Granite Master Angles, Granite Angle Plates, Granite Parallels, & Granite Straight Edges are also available in specified grades and sizes.

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