Bad Piggies Rise and Swine Level 2-28 can be 3-starred using a single contraption. Align three vertical boxes with suction cups on the right side. As soon as you start the level, turn the motors on to climb the cliff face quickly. You’ll grab the star box easily and should be the clock comfortably as well. Just be careful going too fast and flipping the cart.
If you have a different strategy for completing this level feel free to leave a comment below.