It has never been easier to build a complete Great Ball Contraption (GBC) loop yourself! GBC 25 features a mesmerizing module which covers a full loop so the ball flow never ends. Using a more accessible LEGO Set and focusing on one single mechanism this GBC is by far the best GBC to get started.
This GBC is entirely built using only parts from the LEGO Mine Loader and can be referred to as model C of the 42049. This GBC makes sure you master the GBC building techniques and tricks so that you eventually also can build your own GBCs. By default the whole machine is powered by hand but it can easily be upgraded with any LEGO motor (more information in the building instructions).
Master Timing & become a true engineer!
Learn about the wonderful world of mechanisms by building our GBC 25 Sweeper which features a highly efficient, perfectly synchronized ball Push Module. Based on agricultural machinery we have created this GBC Sweeper. Because the whole GBC is on wheels you can hook it up to you LEGO tractor or truck and drive it around.
Balls have to be inserted in the bottom input of the module. The module then picks the balls one by one and guiding them to the next stage. 4 perfectly synchronized push arms work flawlessly together to accomplish getting a GBC ball to the top in one fluent movement. The balls will be pushed out of the rail and return to the base via the return path. By doing so the loop will never end.
This GBC has an extra feature which allows you to easily remove the return path and put your GBC 25 in a bigger loop and combine with other GBC Modules.
Fun Fact
Designing a GBC from such small part inventory really took all the ingenuity and experience we gathered over the years. Parts are being used in a new way and many problems had to be solved for getting this GBC to work and making it sturdy and reliable. Using over 97% of the parts that come with the set we really did get the best and most out of the original LEGO 42049 set. There was a real challenge to build a GBC from such a small set but we succeeded again.
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 25 Sweeper
In the building instructions is explained how to easily upgrade the GBC 25 Sweeper with various parts.
Power & Automate
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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tim –
Bought this as my first one to try out. Works great! See the full review on Eurobricks (https://www.eurobricks.com/forum/index.php?/forums/topic/170165-review-gbc-25-sweeper-42049-c-model-by-pv-productions/)
Violet111 –
got the 20 gbc module too. very different but i like both