I was visiting a small factory recently as part of my job and was very keen to take advantage of the guided tour that I was offered. It is a small family run metal working factory and they produce all sorts of metal objects. I was particularly interested in the way they operate the machinery. They were telling me that they have to buy specialist lubricating fluid for the machines to keep them from being damaged by friction, heat and minute pieces of debris scratching the surfaces. It was a very interesting visit and I hope to find out more the next time I visit.