In college 50 years or so ago, I wanted to make some kind of part for a vacuum chamber, and figured out it would take a lathe. So the library had a copy of "How to Run a Lathe". Got that, read it in an hour or so, and went to see the engineering shop foreman, asking if I could use a lathe, and yes, I was familiar with a South Bend. So he said OK, took me to the lathe. Yep, it looked just like the book, so I set it up just like I thought it should be, and turned it on. Wow, the chuck key flew out about 20 feet and smashed into the concrete block wall about 8' up, near where the foreman was standing. I will always admire and appreciate the way he handled this situation. He picked up the chuck key, handed it back to me, and said "I bet you'll never do that again". And at least through 8:39AM this morning, he's been right.