Watched my Uncle work in a Foundry when I was a few yrs younger. He worked all day making the Moulds. That took a lot of talent itself. They made a lot of didderent things. One was the parts for Gravely Tractors including the cylinders. Everyone took part in pouring the Iron in the evening just before quitting time. That was fun to watch as it was poured by hand. Sparks flying everywhere. We had a Gravely Tractor on the farm and I got to follow a new cylinder all the way thru. He let me clean it up myself. A steel sleeve was inserted after it was cleaned up and all the rough edges removed.