It has never been easier to build a complete 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. It can also to be referred to as the model C of the 42042 Crawler Crane. This module makes sure you master the 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.
Mechanical automation to its max
The loop of the GBC 10 Funfair contains 5 Modules and features in the center the big Ferris Wheel Module. But before we come to that let’s start at the beginning.
The GBC Balls starts at the Horizontal Mover Module which takes one ball at a time and then automatically turns them over 180 degrees to drop them into the next module. To make this work we designed a really effective return/pause mechanism which automatically changes the direction of the Horizontal Mover arm. 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 GBC Balls then go into the big 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.
Building Instructions Preview
Try before you buy. We completely understand. See the building instructions previews on the left or try one of our free building instructions.
Upgrade your GBC 10 Funfair
In the building instructions is explained how to easily upgrade the GBC 10 Funfair with various parts.
USB Power Box
How cool is that!
Learn more!
Get the accessories
We have GBC Balls, handy electronics products and fun accessories available. Take a look at all our accessories!
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Ralf Ter beke –
Love this build. Had so much fun with it.
Rik Mentink –
The building instructions are relatively clear, though when the build is finished I spent an equal amount of time fine tuning and changing the model to make it work. The machine blocks on multiple sub parts and balls keep falling out. It’s fun to build but I expected more of this contraption.
Michael Lam –
HaHa , Final complete this GBC 10 from V7 today , no problem now , all function is work perfect . going to make GBC 9 , GBC 15 , GBC 11, GBC 14 or GBC 12 ……….. every module is VERY COOL !!!!!!
Tan –
Much Appreciate the build. The creativity just amazes me!
jolugoma –
With the recent update (the update to v7), everything works flawlessly.
https://youtu.be/M0nMZ2B3L3U
jolugoma –
Con las recientes modificaciones, todo es mas fácil.
With the recent update (the update to v7), everything works flawlessly.
https://youtu.be/M0nMZ2B3L3U
Michael Lam –
Learn many skill from this model …. very Cool
Michael Lam –
I build this with my 9 years son , he say this is very Cool !!!!!
Johan –
I am building the GBC10 with my 5 yo son. It is a lot of fun.
Alexandre –
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 !
Shawn –
I built this last weekend and got the orange balls today from PV. So much fun during and after the build process
Lucas –
I did it. got it working
Great that they are in pdf so they work flawless on my tablet
勝凱 –
Defi worth building this. love it
Mark –
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!
Patrick –
Wow, just wow!
John –
My grandson and I had so much fun building this together.