Abstract: A method for constructing a metallic collector bar-carbonaceous block assembly for the cathode bottom of an aluminum reduction cell comprising (a) positioning a metallic collector bar within a reduction cell on the bottom surface thereof so that the ends of the bar extend through the cell and connect to an external cathode bus system (b) depositing a layer of binder comprising an electrically conductive, carbonaceous cement onto the exposed surface of the bar, (c) positioning a prebaked carbonaceous cathode block having a transverse slot along its length, in the bottom surface thereof, astride the bar to firmly embed the bar within the slot, the slot having a width exceeding the width of the bar and a depth shallower than the height of the bar.