A method of calibrating an x-ray computed tomography machine provides an x-ray computed tomography machine having calibration settings, and uses the x-ray computed tomography machine to produce a gauge reconstruction. The gauge has a first base supporting two or more objects, and a second base supporting two or more objects. The first base and the second base form a perpendicular configuration, and each of the plurality of objects is secured on at least one of the first base and the second base. Each of the objects has a center, and the distance between the centers of each object is known. The method then measures the distance between at least two objects to produce measured center distance values, compares the measured center distance values against the known center distance values, and uses the comparison to determine if there is a distance error in the gauge reconstruction.