Non-machinable cast iron specialty welding electrodes feature a non-conductive coating that is specially developed for welding dirty, heat-affected and oxidized cast iron. Ideally suited to cladding contaminated casting prior to joining with high nickel alloys. Typical applications include machine bases, pedestals, frames and housings where heat and machinability are not an important factor. Hardness: RC 39. Recommended polarity: DC reverse, straight or AC.