Device for removal of excess material from a test sample

A device for removal of excess material from a test sample, comprising:

• a test geometry comprising a lower geometry and an upper geometry each having a circular outer edge and being centered on an axis of rotation, wherein at least one of the lower and upper geometries is configured to rotate about the axis of rotation;
• a trimming ring having a sidewall, a ring axis coincident with the axis of rotation and at least one cutting edge disposed along at least a portion of a circumference of the trimming ring at a diameter that is at least as great as a diameter of at least one of the lower geometry and the upper geometry, wherein the sidewall is defined by a plurality of fingers each extending from a base of the trimming ring with a gap separating each finger from adjacent fingers, each of the fingers having a cutting edge that is disposed at an acute angle with respect to a length of the trimming ring;
• and
• an actuator coupled to the trimming ring and configured to translate the trimming ring in a direction parallel to the axis of rotation.