In episode 3 of our CNC Machining Action Series, the TRAK FHM7 Bed Mill creates a Euclid Block. The Euclid Block is a test piece we use to check the accuracy of our machines after they are built. We cut the circles (inside & outside) to check circularity, the triangle to check trans-axial movement, and the square to check squareness. Material: 3x3x1 inch piece of aluminum Lubrication: WD-40