Abstract: An apparatus, system, and method using an elastic biasing element in combination with an encoder arrangement for precise control of force or torque applied to a moving object, is applied for controlling a feed force applied to an abrasive element of a bore finishing tool, to respond to changes in the feed force such as can arise from contact with a workpiece bore surface and variations therein, such as tapers, hourglass shapes, barrel shapes, and the like. The elastic biasing element can include a single or multiple springs in one or more sets, and the feed force can be selected to have a constant value or vary as a function of time, position, or other variables or conditions.

Abstract: An apparatus, system, and method using an elastic biasing element in combination with an encoder arrangement for precise control of force or torque applied to a moving object, is applied for controlling a feed force applied to an abrasive element of a bore finishing tool, to respond to changes in the feed force such as can arise from contact with a workpiece bore surface and variations therein, such as tapers, hourglass shapes, barrel shapes, and the like. The elastic biasing element can include a single or multiple springs in one or more sets, and the feed force can be selected to have a constant value or vary as a function of time, position, or other variables or conditions.

Abstract: A drainage unit comprises a first drainage trough and a second drainage trough; said second drainage trough being located adjacent to said first drainage trough; said first drainage trough being configured to attach to a drain cover in order to allow fluid to flow into the first trough; said second trough comprising at least a wall which projects laterally from said first trough; said wall being suitable for accommodating a sub-floor level rail or frame of a door; a number of openings located between said first and second drainage troughs; whereby fluid flows from said second trough into said first trough through said openings. In preferred embodiments, the drainage unit provides an integral level door threshold solution.