• Inexpensive, simple yet accurate device for monitoring crack movement.
• Weather resistant, water proof design permits use in salt water.
• Hot-stamped crosshairs and grid.
The Calibrated Crack Monitor is a simple, accurate device for monitoring the movement of cracks and joints in concrete, brick, or cement block structures.
The Calibrated Crack Monitor consists of two acrylic plates. One plate is white with a black grid calibrated in millimeters, and the overlapping transparent plate has red crosshairs centered over the zero lines of the grid.
After installation, the tape which holds the plates together is cut, allowing the two plates to move independently of each other. Any vertical or horizontal movement of the crack or joint will cause the crosshair to change position on the grid.
A chart is supplied with each gauge for periodic recording of movement. The position of the crosshairs is copied onto a grid facsimile on