Cast iron can be tricky to repair because it’s prone to cracking.
Follow along with Brandon Lund as he repairs a broken cast iron exhaust manifold using Muggy Weld with no pre-heat.
Although I believe a good pre-heat and a slow cool down will give you the best chance for success, I wanted to see how this rod would respond in a worst-case scenario, such as cold welding. It handled the thermal stresses excellent without any signs of cracking. This would be a huge bonus for parts too big to get a good pre-heat / cool down or for parts that are not cost easily removed.
For this demonstration, Brandon used a 2 step process starting with an electrode that can withstand the dirtiest of cast irons followed by a cap that has excellent crack resistance properties…