Shipping container windows cut out safely. These have a LOT of stress on them.

This video looks at how much the metal will deflect when you remove any of it from a shipping container wall. This creates some special concerns - the metal might punch out enough to strike you pretty hard. In addition the tools will likely get pinched in the cutouts and it is important to have the proper safety equipment and to also be ready for kick-back / kick-out. I cover how to followup with a flapper disk to grind the sharp edges. Although I am thinking a conduit deburr tool might be faster and easier. Lastly, I cover how to add structure back into the missing hole and transfer all that energy and deformity back into the structure of the corrugated side walls.