A couple of weeks ago, at a car boot sale, I bought 3 flat irons as a potential source of cast iron. The first thing that I did with them was to put them in my furnace and heat them up to red heat and then allow them to cool overnight just in case that they had been chilled when originally cast.
Today I wanted to make a chuck backplate for a small lathe that I am making. I trimmed the first one down to a squarish shape with my trusty angle grinder and popped it into the four jaw chuck on my lathe. After facing it off I was surprised to see that it had four large cracks (only 3 to be seen in the photo) making it useless for this project, although there is enough uncracked material for future smaller projects.
I tried again with the next one and was delighted to find that it had no cracks. Mind you it is tough material, I could only take 5 thou deep cuts otherwise the belt would slip on my flat belt drive lathe. When you consider that I was using an irregular shaped piece of iron there was a lot to remove before I got to a round shape, but it was worth it!
