Quoted By:
For example, this Duplo engine block will stack on a regular 2x2 Duplo block, but because of the shape of the bottom lip, it won't stack on a 4x4 System plate. To get around this, I have a 3x4 area of System studs with a 1x4 tile along the edge, which makes the 4x4 area and keeps it tight enough.
