"In this video we build a simple photoelasticity setup with polarizing filters, a light source, and high-speed cameras to see the internal stress patterns inside plastic parts as they bend, crack, and explode under pressure. In other words: science, colorful stress lines, and total destruction. We test different plastic items with the hydraulic press and try to capture the exact moment when the internal stress becomes visible right before failure. The result is one of the coolest-looking stress experiments we have done. If you know the science better than we do, explain it in the comments ???? Want even more stress science? We also made a more technical video about measuring stress inside metal parts with X-rays on Beyond the Press. We also still have a few spots left for our Finnish Summer Mayhem Vacation, where one day is spent at our workshop crushing stuff live. More information here"