The actual making of them goes fast, about an hour, after their design is on paper. First they are drawn to scale, then transferred to carboard or foamboard, cut, and glued together. Unfortunately I couldn't find my LuSiD's proto.
Building the model first means that I must know the geometry of the cabinet, so I can put the outside and inside corners in their right places when the real one's built.
Glad you liked them!