Testing Products for ASTM D1781

This standard is unique for its use of a climbing drum apparatus to evaluate the peel resistance of adhesive bonds between flexible facings and rigid substrates. Unlike standard 90° or 180° peels, the rotating drum maintains a constant peel angle and minimizes substrate bending, making it the benchmark for aerospace sandwich panels. The Newton-Series controller is vital here for its ability to perform a Tared Torque calculation; the system must subtract the energy required to lift the drum itself from the total recorded force to isolate the true adhesive bond strength. Accurate reporting depends on analyzing the Steady-State flat portion of the curve, ignoring the initial peak during crack initiation. This data is critical for validating structural integrity in flight surfaces where delamination could be catastrophic.