How to Identify Cast Iron, Ductile or Grey Iron

I have three different ways I like to identify cast iron. It's always hard to tell by just looking at it. I use a drill, grinder, center punch, and hammer. It's important to know what kind of cast iron your're working with because each requires a different weld process to fix. Let me know if you want a video about the fix process for both. Thanks for watching and I can't wait to show you whats next.
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