Bond strength tester with switchable backlash control

A testing apparatus for testing the strength of a material connection to a substrate, comprising:

• a main body,
• a test tool mount for holding a test tool,
• an axial drive mechanism, the drive mechanism coupling the test tool mount to the main body and allowing for relative movement between the test tool mount and the main body in an axial direction, and
• a biasing element, coupled between the main body and the test tool mount, that, in operation, biases the test tool mount relative to the main body in an axial direction, wherein the biasing element is switchable by a user between a first state in which the test tool mount is biased either toward or away from the substrate and another state in which the biasing element provides one of:
• no biasing force to the test tool mount toward or away from the substrate, or a biasing force in a direction opposite to the direction of bias applied in the first state.