When I was in high school in CA I took metal shop. This was in the early 60s. The shop teacher taught students how to sharpen a knife and how to make knives. My first knife I made from a old file. I put it in an oven to take the temper off. I took off the cutters and shaped it. Put it back in the oven until it was at the temp the teacher said, then used an oil quench. It holds a decent edge. If a teacher tried to teach these skills today he would loose his job and have parents try to have him jailed.