Tell Tale Plus
The Avongard Tell-Tale Plus monitors horizontal and vertical movement across a crack on a flat surface. The Tell-Tale is pre-set at zero with four pegs. The pegs are removed after the Tell-Tale is fixed across the crack.
Avongard Tell-Tales are precision gauges that consist of two plates which overlap for a part of their length.
The bottom plate is calibrated in millimetres and the top plate is transparent and marked with a hairline cursor in the form of a cross.
Supplied with full instructions and Crack Record Sheet (Replacement Crack Record Sheets can be downloaded from here).
Monitoring Cracks to +/- 1.0 mm accuracy
As the crack opens, or if vertical movement occurs, the cursor moves relative to the calibration scale. The opening or closing of the crack is then recorded on the crack record sheet supplied.