Electrical discharge micro-drilling uses tubular section electrodes with diameters starting at 0.09 mm (90 µm). Larger diameters are drilled by planetary movement of the tool. Smaller diameters can be drilled by a micro-electrode which is machined by a device which is integrated in the micro-drilling machine.
Minimum surface roughness : 0.1 Ra
Minimum drilling diameter : 20 µm
Minimum electrode diameter : 20 µm
Diameter accuracy : 5 µm
Center distance accuracy : 2 µm