The ferrous metals that you need to know about are cast iron, mild steel and carbon steel.
Cast iron - There are two types: White cast iron and Grey cast iron.
White cast iron is not easy to work with as it is hard and brittle. Grey cast iron is the most useful. This material can be cast into intricate shapes and is often used for components on machines such as the trail stocks on lathes. It is a material that can be machined and when compared to steel it is relatively corrosion resistant.
One downside of cast iron is that it is brittle and will shatter…