It has never been easier to build a complete Great Ball Contraption (GBC) loop yourself! The GBC 19 Log Flume attraction is way bigger than the original LEGO model and it features multiple GBC modules which all work together in harmony to make a full loop so the ball flow will never end. With over 2000 parts, 300+ pages of building instructions and a footprint of a whopping 100 cm (40 inch) by 50 cm (20 inch) this GBC is one of the biggest GBCs we have ever created.
This GBC is entirely built using only parts from the LEGO Mobile Crane MK II and can be referred to as model C of the 42009. This GBC makes sure you master the GBC building techniques and tricks so that you eventually also can build your own GBCs. The whole machine is powered by one LEGO motor which comes with the LEGO 42009 Set.
Open your amusement park today!
Ever been to Disneyland or another amusement park? We bet you have!
The GBC 19 Log Flume attraction is inspired on one of those fixed track cart rides which gives the visitors (a.k.a. our GBC balls ;) an awesome ride experience. Watching the elegant and smooth turns the carts make in the corners as well as the clever mechanisms that they trigger is really a feast for the eyes. With 3 carts included, GBC 19 can handle a lot of GBC balls at the same time. All carts start at the station where also the engine and control room are located. A powerful geared and carefully designed drag system pulls the rope, on which the carts are attached, forward. The user can simply adjust the gripping force on which the gears and tire grips on to the rope. After the first turn to the right the carts will trigger the filling mechanism which carefully lets up to max 6 GBC balls in the cart at a time. On the next turn the carts are facing a hill with an epic door system at the top. Coming closer and closer near the top, the closed doors magically open like they do in all Jurassic Park movies.
Of course we know better and an efficient mechanism, triggered by the cart, kicks into action which opens the doors automatically. When the cart is through the doors, they close again for the next cart to enter. Halfway through the ride, when on the highest point, a guidance rail triggers the mechanism on the cart itself which tips the balls out of the cart. The cart then returns downhill back to the station. The balls however are guided back by a side track which brings them back to the input of the GBC. In this way GBC 19 is self contained and the ball flow never stops.
It is made easy to take out the ball back guiders so you create an in and output according to the GBC rules. In this way you can easily connect this GBC to all our other GBCs to make the loop even bigger.
It is possible to move the whole structure at once when you hold it right. However, advised is to place the GBC on a solid plate or to disassemble the GBC in separate modules again when moving the GBC.
Last thing to do is to build this GBC and perhaps build your own ride design /theme around this structure!
Important note: Next to the LEGO 42009 parts you also need 6 regular rubber bands (size and strength doesn’t really matter, more info in the building instructions).
Fun Fact
The cart went through 22 different designs before ending up with the final build. Taking care of the looks/colors and functionality around the whole track limited by the 42009 part set we are eventually very pleased with the end result.
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- LEGO 42009
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- GBC 19 – 42009 C Model
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- GBC 19 – 42009 C Model
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- GBC 19 – 42009 C Model
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- GBC 19 – 42009 C Model
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- GBC 19 – 42009 C Model
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- GBC 19 – 42009 C Model
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- GBC 19 Control Room Station
Building Instructions Preview
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 19 Log Flume
In the building instructions is explained how to easily upgrade the GBC 19 Log Flume with various parts.
USB Power Box
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ramon –
I was amazed when I saw the video of this. I instantly wanted to build this. It’s pretty straight forward to build, as long as you’re not in the final phase where you need to adjust the rope and the rubber band. I tried quite a few things to get it run smoothly, but didn’t got it to run more than some minutes until the rope would stop, the cars would leave the track or the rubber bands would stretch too much. It is very tricky to set up. Even some own ropes did not do the job very long.
It’s still a very remarkable build – I like the track with the rectangular corners very much and how the cars drive through.
But be aware that the adjustment takes quite some time and maybe several atempts. I needed to run it for 1 hour, which was by far not possible.
A very beautiful build! With tricky setup! If you take the challenge with enough patience you will have a lot of reward!
Sugiarto Pangestu –
Great engineering using available parts from 42009. Instructions are about 300 pages but could be shorter if some left/right parts are combined. You better build this part on a removable base or on a table. The structure is not rigid enough for you to bring around when fully assembled.
You may need to adjust some gears on the automatic door and ball dropper few times before the mechanism works as intended. By far the most difficult part of this build is the whole “rope and rubberband knot”. If you tie the knot too much it will derail when the knot goes through the “tan” colored gears. Meanwhile if the knot isn’t secure enough, the rope will get pulled out after several laps eventually. Don’t even get me started on the rubberband knot.
Suggestion:
Unused 2pcs Lego String with end studs may be used to secure both the ascending track and descending track so they do not have gaps.
Common household heatshrink-tube wrap can be used and formed to conceal the remaining rope. This is important as you have to leave some length of rope behind the cart to prevent it getting caught in some places.
Kian –
amazing automation engineering. Love the automatic gates. Finally a good use for my MK2 haha