The GBC Standard

What is the Great Ball Contraption standard?

The GBC standard is a set of rules that allows for modules of all shapes and sizes to be brought together to form a collaborative GBC Layout.  If the rules are followed, a GBC  layout made up of many modules should be able to pass balls around without having to make major changes to any module.

Who created it?

From what I can tell, the GBC Standard was created by Steve Hassenplug in 2005, with Brian Alano (aka ALittleSlow) holding the registration for  There are probably more people involved but I'm really not sure.

What are the rules?

  1. Each module should have an "in-basket", and will move balls to the next module's in-basket, which must be directly in line.
  2. The in-basket should be 10 studs by 10 studs (outside dimension) with an 8-stud by 8-stud opening, and should be 10 bricks tall.
  3. The front of the basket should be 32 studs from the back of the module. This will allow all modules to be lined up against a wall. The back of the module can be closer to the basket, but not farther.
  4. The in-basket should be located on the left side of the module, and output should go to the right.
  5. There are no size limits beyond those listed.
  6. Each module should be able to accept balls at an average rate of 1 ball per second. Balls can be passed continuously, or in a batch. A batch should not exceed 30 balls.

These rules can be seen in detail over at:

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