An improved method of operating an arc furnace is provided. The sidewall of the furnace includes a refractory lining. A charge of scrap metal is added to the furnace. The charge is melted and a slag layer is formed on the top of the melting charge. The furnace is tapped at the bottom to remove a portion of the melted charge. After tapping the furnace, the slag is splashed onto the sidewall to thereby coat the sidewall with a frozen slag layer.