Welding cast iron can be tricky but it is possible. Here are some steps you can follow:
1. Preparation - Beveling or drilling holds before and after cracks, cleaning the surface.
2. Amount of heat - Always low and slow.
3. Selecting the right rod - More nickel the better.
4. Change in temperature - Heat the metal in MIG welding and cool it down to room temperature and let it solidify. Cast iron contains high carbon and, therefore, has an increased brittleness. Any sudden temperature change can make it shrink or expand, causing it to break down.
You can find more detailed information on how to weld cast iron in the following links:
- [The Welding Handbook](https://www.weldinghandbook.com/how-to-weld-cast-iron/)
- [Water Welders](https://waterwelders.com/how-to-weld-cast-iron/)
- [Welder Stream](https://welderstream.com/how-to-weld-cast-iron/)
- [Welder Academy](https://welderacademy.com/mig-welding-cast-iron-a-step-by-step-guide/)
