We claim the ornamental design for a 3D printing post processing station, as shown and described.
FIG. 1 is a front right perspective view of a 3D printing post processing station;
FIG. 2 is front left perspective view thereof;
FIG. 3 is a front view thereof;
FIG. 4 is a rear view thereof;
FIG. 5 is a right side view thereof;
FIG. 6 is a right side view of FIG. 1, with broken line subject matter omitted;
FIG. 7 is a left side view of FIG. 1;
FIG. 8 is a top view thereof; and,
FIG. 9 is a bottom view thereof.
The broken lines immediately adjacent to the shaded areas and define unshaded regions depict the bounds of the claimed design, while all other broken lines are directed to environment. The broken lines form no part of the claimed design.