MOC: Harbour Crane, 42043 C model

Overview:

A model of a typical harbour crane built only using parts from set 42043 (and a winch and a small wheel). About 1000 pieces were left over from the 2793-piece set. This MOC turned out alright but suffers from a balance issue. To allow the superstructure to slide, the base had to be small to not limit its range a critically small amount. Because of this it could bend easily, and so with any load shift, including the lifting and lowering of the boom, the superstructure would sway back and forth. Therefore, the load capacity was only about 200g.

The model has 6 functions, 3 powered and 3 pneumatic. The power functions are superstructure sliding, superstructure rotation, and the winch. The pneumatic functions are boom lifting, cab tilting, and grabber opening/closing. As you can tell from the picture, I tried to include lots of details, such as the walkways and lights. (These details are mostly inspired by the 42055.)

Build process

The build started with a base and the gearbox. Weirdly enough, everything worked out just fine with them and both are featured in the finished model (with very minor changes). Unfortunately, some disbalance is alredy visible.

Next up is the boom, to see how disbalanced everything would end up. The boom balanced the gearbox just right so I had no worries upon adding it. The Linear acutator would eventually be removed, along with the entire gray segment. The whole thing looks like the base of a luffing crane so far.

Then I didn't feel like thinking about mechanism so I quickly added the rest of the boom (including the grabber) and started with the tubing. Now, with the grabber, some disbalance toward the front while the boom was lowered is evident. I would eventually add the battery box and pneumatic mainframe so I thought everything would work out, but I was really wrong.

Next up, the pneumatic mainframe. It's simple, but meant a lot of tubing stuffed into a tiny space, the upper house. The battery box was also added. The combination of these 2 factors completely ruined the balance. When the boom was raised the superstructure tilted backwards, and vice versa.

At this point accuracy was a worry since this was one of the last stages of the project, so I removed the LA and added a winch so it is now more of a harbor crane.

And now, the project was virtually done, but the boom looks terrible and the whole thing is just a luffing crane. So I removed all the gray segments and redesigned the boom (which is a stretch on the amount of red pieces in the set) but it was worth it.

Conclusion

In the end, the crane still suffers from the balance issue. But, thankfully, all the functions work well, so the crane is fully operational. That's all for now, stay tuned for more MOCs!

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