150 d between and perpendicular to first and second flat surfaces 150 a and 150 b has been ion milled into conical tip 135 again using for example a focused ion beam on the extreme end of conical tip 135 thereby removing any contamination and or oxidation and exposing a second clean new surface milling fourth flat surface 150 d does not require removing probe 110 from the ion milling machine focused ion beam after milling surface 150 c but merely rotating the probe 180 u00b0 relative to the beam axis see fig1 and 12 after the fifth milling step reconstructed probe 110 a having a new square pyramidal tip 155 having a new point 160 has been formed point 160 is the apex of the pyramidal tip 155 remnants of old conical tip 135 remain between shank 140 and tip 155 alternatively all of old conical tip 135 may and even portions of shank 140 may be milled away so no surfaces of conical tip 135 remain the process described included after milling flat 145 see fig4 a milling surface 150 a rotating probe 110 180 u00b0 milling surface 150 b rotating probe 110 90 u00b0 milling surface 150 c rotating probe 110 180 u00b0 and milling surface 150 d alternatively the process may include after milling flat 145 see fig4 a milling surface 150 a rotating probe 110 90 u00b0 milling surface 150 c rotating probe 110 90 u00b0 milling surface 150 b rotating probe 110 90 u00b0 and milling surface 150 d fig9 is a top view of a wire probe after reconstruction according to embodiments of the present invention in fig9 shank 140 has a diameter of d 1 the base of.