How To Weld Cast Iron With A Torch. Even before you begin thinking about welding cast iron you must identify clean preheat and select a welding technique. One is called preheated welding and the other is called non-preheated welding.
Amount of heat always low and slow. Use a proper welding rod. Take your time heating it.
Generally preheated welding is performed by heating the cast iron from 500 to 1200.
Heat or cool slowly. Tips to Get the Perfect Weld Cleaning Surfaces. Generally preheated welding is performed by heating the cast iron from 500 to 1200. However there are basically two approaches by which you can weld cast iron.