Five-Face Granite Master Squares are popular for accurately checking the X-Y-Z axes on CNC machine tools and coordinate measuring machines. Lying in the horizontal position, the X and Y axes can be checked for 90º squareness. With the square in the vertical position, tracing along the vertical edge of the square can check the perpendicularity of the Z axis. By tracing along the top edge of the square while in the vertical position, it will check parallelism of the table in the X and Y axes to the spindle. Five-face master squares may also be used on any work that requires the checking of squareness or parallelism.

Granite Master Squares - AA Grade - 5-Face at

5-Face Granite Master Squares include 1 large face along with 4 edges that are flat, square and parallel to each other, and also includes lightening holes. The number of lightening holes included will vary with the size of the square.

These Granite Master Squares are made of black granite, which is stronger and denser than light colored granite, and is also more stable, providing more accurate and more repeatable measurements.

These 5-Face Granite Master Squares are available in 2 Grades...

  • AA Grade is also known as Laboratory Grade
  • .000050" Accuracy
  • A Grade is also known as Inspection Grade
  • .0001" Accuracy

Each Master Square includes a Certificate of Calibration Traceable to NIST.

  • An ISO 17025 Accredited Cert is available at an extra charge.

sHOP our Granite Master Squares - AA Grade - 5-Face collection...

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