LEGO GBC 10 – 5 Modules – 42042 Building Instructions

15.95 12.95

Detailed building instructions of the LEGO GBC 10.
Made from parts of LEGO Crawler Crane set 42042.

– Full HD PDF building instructions
– Brief with tips & tricks
– and more

Difficulty level: Easy – Medium – Hard

Product Description

Example Full HD pdf Building Instructions

It has never been easier to build a complete LEGO Great Ball Contraption (GBC) loop yourself! This GBC is entirely built using only parts from the LEGO Technic Crawler Crane 42042 set and uses 95% of all the pieces that come with it. Also to be referred to as model D of the 42042 Crawler Crane. This module makes sure you master the LEGO GBC building techniques and tricks so that you eventually also can build your own GBC. The whole machine is powered by one LEGO motor which comes with the LEGO 42042 Set.

This GBC works great with our LEGO GBC balls.





The loop starts at the Horizontal Mover Module which takes one ball at a time and then turns them over 180 degrees to drop them into the next module. To make this work we designed a really effective return/pauze mechanism which automatically changes the direction of the Horizontal beam. The next module is the Conveyor Belt Module which brings the balls up to the Flip Flop Module. This module separates the balls equally over 2 bins. When a bin is filled up to 8 balls it will automatically empty itself and release the balls back into the loop.


The balls then go into the Ferris Wheel Module which is fully mechanical automated. The ferris wheel has 4 cabins each holding 1 ball. The timings mechanisms, which releases one ball in one cabin, uses a specific gear ratios to get the timing right every time. The timing of entering balls into the cabins comes quite precise but when you have the timing just correctly everything works like a charm. After 3/4 of a revolution on the wheel the balls drop of and continue the loop by starting at the begin point again.


Batteries can easily be replaced. If you are out of batteries you can also power the whole GBC manually by turning the yellow handle.


NOTE: You may not reupload the building instructions.





The LEGO GBC Balls are available HERE.














LEGO GBC 10 all over the world





LEGO GBC 10 at fair

Did you also built one of our LEGO GBCs yourself, with your friends or family? We would love to see and share it! Send us a picture or video at or via our social media channels.


This GBC is in collaboration with SAM Labs Electronics.

Want to add cool electronics to this GBC? We used SAM to sort out different color balls.
See the SAM version of LEGO GBC 10 here.


SAM Labs blurb:








SAM LABS Electronics is a library of smart electronics modules connected to the Internet of Things. SAMs, as the modules are called, consist out of sliders, buttons, motors, lights and much more. Getting interested? See also more awesomeness at their website.








8 reviews for LEGO GBC 10 – 5 Modules – 42042 Building Instructions

  1. :

    My grandson and I had so much fun building this together.

  2. :

    Wow, just wow!

  3. (verified owner):

    Service from PV Productions has been excellent with great communication. I have received the instructions but haven’t built the GBC yet. I will post another review of the build once completed. It looks great… I may stop building the original crawler crane so that I can build this!

  4. :

    Defi worth building this. love it

  5. (verified owner):

    I did it. got it working
    Great that they are in pdf so they work flawless on my tablet

  6. (verified owner):

    I built this last weekend and got the orange balls today from PV. So much fun during and after the build process

  7. (verified owner):

    Built it with my two children (4 and 10 years old). Received my balls today and fine tuned all the machinery this evening. They keep on saying “waw”, “cool”, “waw”… And so am I ;-) Very impressive conception. I’m so satisfied and curious about getting into a bigger GBC I just bought another instruction (GBC12). Maybe will I try to connect both… Thanks !

  8. (verified owner):

    I am building the GBC10 with my 5 yo son. It is a lot of fun.

Add a review