Industry, near L.A., making cardboard boxes of all sizes. I made about 5 times the minimum wage per hour. The hardest part of the job was when I was working on the commercial cardboard corrugating machine (see picture for a typical machine) that makes the corrugated cardboard from the roles of paper, gluing the layers together, heating the corrugated results, then cutting the paper into widths and lengths.  Often I worked at the end of the machine, squaring up the cut pieces and stacking them on a pallet. The first two weeks were a killer handling freshly cut cardboard. My hands were loaded with paper cuts that took about a week to heal. There was no way to wear gloves and properly handle the pieces. The hardest job was handling the cut lengths for the army's C-ration boxes. There was no corrugation so there was no spacing between about 5 layers of paper for the heat to escape. Plus C-ration cardboard was waterproofed, which caused my eyes to burn. But it was easy to beat the time quota and make a nice bonus. A summer working there paid for most of my school and living expenses at BYU. I worked there two summers. They called my parents house one summer to see if I was going to work that summer, but I was on my mission.