If you had asked me a few years ago what the most valuable asset in my machine shop was, I probably would have pointed to my largest CNC machining center or one of my precision lathes. After all, those machines generate the revenue that keeps the doors open. Today, I have a different answer. The most valuable investment I have ever made is not a machine at all. It is the time and discipline we put into maintaining every piece of equipment in our shop. I learned that lesson when I applied for a bank loan to expand our operation.…