The cart placed in the artwork. The downward angle will change as the shaft length has been increased. The model was built with the cart upright. For example, the shaft is perfectly horizontal. The plane is used as a “Jig” for placement of the cart. Placing the 3D cursor in the center of the right wheel, and change the view to Shift-Ctrl-Num3, rotate (pivoting on the 3D cursor) the cart until the shaft breaks the terrain (in this case, about half of the shaft). Then Shift-Ctrl-Num7 for a top view and rotate 12 deg.

