If you zoom the picture to Original size, you should be able to see the pencil markings on the far end of the sheet. This is the first time I've worked with a 4x8 sheet of styrene! A nice smooth piece of maple plywood I had around makes a good worktop, located on top of my pool table with a few 2x4 pieces as supports underneath. Not the angle iron to be used as a cutting straight edge, clamped to the surface.