The model uses something like 75% of the parts and, crucially, the new parts in it are used only for cosmetic purposes so if you have enough Technic laying around you might be able build the actual mechanism without resorting to dismantling the BWE or buying another set. A third conveyer sits at the bottom of the input chute. It moves much slower than the output belts. This is definitely a model that benefits from a video review but they are thin on the ground on YouTube at the moment. If I wasn't hopeless with a video camera I would have had a go myself. However, we still have not finished construction... At the end of bags #7 the model is functionally complete and can be tested and I urge you to do so because if there is any debugging to be done it will be more easily achieved now. It's massive! The arm is 75cm long. It stands 45cm high. It's 28 cm wide. There are a lot of nice finishing touches: the walkways, handrails, lights, ladders and so on which enhance its appearance considerably.

Following on from that, the rear end of the digging arm is constructed which includes the control panel/gear box. Here you can see the innards before they are hidden by the top panel. Light Bluish Gray Electric 9V Battery Box 4 x 11 x 7 PF with Orange Switch and Dark Bluish Gray Covers The driveline for driving, turning and the small conveyer belt are also connected with these parts. Here it’s more obvious. The parts don’t hold tight to the axle but can slide. This allowing some wiggleroom when lowering and raising the big arm. It's a long satisfying build and the finished model looks great, but how does it operate? Unfortunately this is where it's a bit of a let down. The first thing to bear in mind is that you will need nearly all of the parts to hand to build it because, unlike the main model that's built from numbered bags, to build this you need to open all of bags #2 - #8 and sort the parts before you start. Consequently you'll need a very large area to work on.Having now built it, I can confirm that it is indeed an impressive machine, but it's really pushing the limits of what is possible with the Technic system and one motor...

That's the theory anyway... It's a neat mechanism and it almost works. Generally, the 2x2s always exit the machine correctly but the 1x1s often don't.Note: I took the pictures outside in the garden this morning so they have a nice 'warm' tone to them.) This is definitely a set that benefits from a video review so I encourage you to watch Sariel's. You can skip past the unboxing and construction to 17m 30s to see the machine in operation. It's somewhat front-heavy so there is a bit of a tilt on the body which results in the vertical frame not being exactly vertical. It doesn't seem to interfere with operation though. Relatively cheap (yes, I’m dutch). In this set the parts are about € 0.06 cent per part. In for example the Porsche this is € 0.12. After 225 steps and about 3.5 hours of building the chassis and lower part of the body are complete.

The left-hand output conveyer in the image below can be raised and lowered using gears on the side, while the one on the right can be rotated about 180 degrees. Step 4 builds the structure that carries the 2 arms. During the build I wondered why there were Technic Wedge Belt Wheel (4185) sitting in different angles at the bottom. There were no belts in the inventory, so I was unclear of their use. The box is the biggest I’ve ever had (42009 and 42030 being the largest yet for me). It measures 57.8 x 47.8 x 16.8 cm and weighs 5970 gram. On the front the main model. Basically, as the conveyer moves an 'agitating plate' is raised when the 1x5 beams on the belt pass under its end, which then drops again once it has passed. This in turn causes three axles under the input chute, mounted at a slight angle and spaced to allow 1x1 rounds to pass through them but not the 2x2s, to move up and down/vibrate as well. The 2x2s travel on top of the axles to their exit on the left (in the photo below) while the 1x1 fall through to theirs, on the right. You can see the ends of the three axles in the picture above. Upload an Image in the specific color if you have one and the one in the above listing is not available.

The 1x1s often just sit on the agitating plate and sometimes never exit. This is because (a) they are not spherical and (b) the plate is not completely smooth, so depending on how they land, they don't always roll down it. The plate's up and down movement is not sufficient to encourage them to move! Die-hard Technic fans will want it regardless but if you are on the fence or have limited funds, there are much better Technic sets released this year that I would buy before this one.

Thanks to Evvilspoon, who's also built it, for confirming that it was not just my model that had problems with the 1x1s. After experimenting this morning, I found a simple fix for the latter problem which doesn't solve it fully but does improve things considerably: Step 8 completes the model with the cabin, railing and other small stuff. The cabin is a little too small for a minifigure. Step 2 builds the bottom part of the frame, on top of which the rest can rotate. I found this part a bit boring. Everything is double symmetrical, so often you have to build the same thing twice or four times.So, how does it work? Quite cleverly as it happens, but unfortunately the mechanism is buried deep inside the machine so is impossible to photograph without a major dismantling. (Yes, I should have photo'd it before finishing it, I know...) I am therefore not able to wholeheartedly recommend this set: Personally I think it's pushing the boundaries of what's possible with Technic, particularly the Power Functions system, a bit too far and the model has suffered as a result.