Lego® 2x4 Brick

Mostly for testing X/Y/Z calibration. The internal side-to-side vanes don't connect properly, and there were a few strings between the internal cylinders, but this mounts firmly on a real 2x4 brick. Although I have "brim" turned off, the first layer of the brick oozes out a little bit beyond the intended spot, so you have to trim the bottom (top) of the brick to get it to fit cleanly between real bricks.