Great Ball Contraption Set-ups and Examples:

In the examples below, a small dashed box represents a module's "input bin", while an arrow indicate where the module outputs the ball stream. A module must have:

  1. The output opposite the input, and in a straight line
  2. The input on the left, and the output on the right.
  3. The front corner of the 10x10 input bin must be 32 studs or less from the rear of the module (to put it another way, a module cannot be deeper than 32 studs behind the front of the input bin). Also, it's preferable (although not mandatory) that modules be longer (left to right) than they are deep (front to back):


Here's a short sample layout - the first module is assumed to be 32x32. Notice that module #4 (marked with an "X") does not follow the standard, as it's rear edge is more than 32 studs from the front of the input bin, but modules #2 & #5 do (they are under the limit):


Within hours of the first announcement of the GBC standards, people started suggesting ways to modify the standard to allow turns. It was quickly realized that both left and right turns could be constructed without modifying the standard. For instance, the first set-up utilizes three modules that all follow the standard to form a "normal" GBC. In the second diagram, these same three modules are arranged to allow a right turn and then a left turn