Ga zuciyar ƙarfe, ana buƙatar zanen tsakiya ya zama lebur, babu raƙuman ruwa, ya kamata ya kasance a tsaye bayan ya tsaya, ba a karkace ba, tsari a bayyane yake, haɗin yana da ƙarfi, daidai ne, gefen yanki ba tare da gajeren da'ira ba, da sauransu, don tabbatar da aikin lantarki na tsakiyar ƙarfe.