Hitachi CX700GLS drilling rig

Why this machine?

A drilling rig for screw bearing pales: not really something which occur when you want to build something high. Most times you're thinking about a mobile crane. As I wanted to build 'something different' I decided to put a certain machine into hands.
Late December 2000 I started to build a brand new Hitachi CX700GLS of the in the North West of the Netherlands based company Vroom. I was thinking of something after I got a tip that this machine was operating on a construction site in a town nearby. A few weeks before I started the construction I took some pictures of the machine and I asked for information to get started. The machine would be loaded onto a low loader truck. The scale of this LEGO model is 1:13. The was some time preceding the result. You can read everything about it in the story below.

For an extensive description of how the model is constructed, I refer to the website of Vroom. There's only one problem for those who can't read Dutch: the complete text is in Dutch. But there are many pictures to be seen. On my own website I only talk about the headlines.

The model

A machine on a crawler tracked undercarriage is always fine to build. In '96 I already built a Hitachi KH180-3 dragline, but this machine constrast sharply with the CX700. That time I didn't had the knowledge about certain machines. Later, in '99, I built my first drilling rig, a ordnary drilling rig. The base of this machine is compared to the crawler crane I built in '96. Though, the machine was of the same type. But for the second time I still didn't had the knowledge necessary: it became a static model. But it reached a maximum height of three metres. The only reference I had where some few pictures (of the machine on transport) and some images from trade journals.
With the CX700 I put the helm completely over: first I studied how the machine exactly works. With that I made numerous detailed pictures at the construction site. On the spot I looked at every function of the machine. For example where all cables serves for. At home, when the pictures where processed, I worked everything out in drawings. Those drawings formed the base for the construction of the model. In a meanwhile I had asked for documention and drawings at Hitachi and they also brought me a step closer. I needed a 1:50 scale model of a Hitachi dragline to determine the dimensions of the superstructure. In combination with the pictures it served very well and I think the proportions are good. It's nearly impossible to build it exactly as the real one, but I always want to reach the reality as far as possible.

The undercarriage is simple to construct: two crawler tracks connected to a turntable. The drive of the turntable comes straight from the Liebherr crane, allthough, it's an exact copy of it (the one from the crane I put into the excavator). The crawlers are connected to two traverse beams. The undercarriage can be extracted. Court of first instance it couldn't extract far enough. But after some changes it agrees with the real one.
After the undercarriage I started with the superstructure. It really is chuck full of axles and gears. Especially the right side is very well filled. Because off lack of powerfull motors and space in the model to drive three winches I put a gear change (from set 8479) into the Hitachi. Via the gear change you can connect four functions on only one drive. Te drive consist of two connected 12V motors. The four functions are:

	the luffing mechanism of the leader
	main winch
	secondairy winch
	the lifting mechanism of the leader (function adapted later)

In spite of the multitude of gears it works perfect. Mainly because I sprayed lock spray between the axles. It all spins smooth. The three winches at the front are driven separately by three 12V motors.t These serves for the work lift, a net hoist and the hoist for e.g. dragline partions.
The operator's cab is fully equiped with e.g. a set of instruments for the operator. On the door it stands proudly 'Driver Cor'. The ballast (the yellow-black striped part) consist of three pieces: two separate blocks and a main block. The main block is mounted to the machine but it can be separated. Both separate blocks are put away during transport.
Behind the machine a table is mounted. On the table a power pack is put. It takes care of all necessary power supply and is driven by a 800 hp (!) engine. It also takes care of some ballast and for this model that's really necessary. In the power pack I put a compressor which serves the pneumatic pad jacks at the back of the machine. Although the model is quite heavy two cylinders are strong enough to hold the weight of the upperstructure without the powerpack. The leader is luffed with the help of cables. Within ten minutes it's errected (with 2.2 metres leader). The machine can luff the leader on its own power. With a leader of three metres length, you'll have to give some supports. But in real life the machine also gets some support by a mobile crane. The leader consist of six segments. The under part is mounted to the machine. All other segments are hauled by other trucks from construction site to construction site. On top of the leader a head part with fourtien shaves is put. Over the head part are permanently four functions ( drill engine, net hoist, lifting mechnism, work lift). Especially when setting up the machine this really takes some time. All leader segments are mounted together very easy by technic bricks. It the leader is luffing it bends a lot. But when it's all plastic this isn't surprising. Do you know how it looks like in real life?

How does it work?

In the leader hangs a drill engine. The drill engine provides that it's possible to create a pile on location sound and vibration proof. Normally and ordnary drilling rig thumps the concrete piles into the ground. But those machines may not operate on civilized location because off the noise nuisance. The proces of my drilling rig is as follows:
During the (not rotating) pull out of the drill the concrete is flewing via a concrete pump through the core of the drill engine and the drill. The concrete is flewing to the screw continuous. The hole which is drilled in the ground is filled with mortar. The propeller blades are stripped of the came out ground. The concrete screw system is, just like all other screw systems, vibration and sound proof.

In the drilling engine there's a 4.5V motor with two round reduction units. These provides the correct speed of the drill. The drill engine weights about one and a half to two kilos. That's a whole weight to lift up. But that's no problem for the machine. The only problem is that the drill engine can stuck in the leader because off the neads between two parts of the leader. That's why the drill engine felt out of the leader one time. Several pieces where serious damaged because off the weight. Fortunate this machine has never crashed, in comparissing to the Liebherr crane. After building some high creations you get some skilled in this field. You know how far you can go, where your limits are. I think I almost have reached the maximum of the LEGO pieces. It can't be higher you should say.

Setting it up

To set this machine up you have to carry a lot of components. The picture underneath shows all components of the Hitachi. At home it's not that big problem because you've got everything on your side. But when you are on a model show, you'll have to be sure you've taken everything with you. All small parts (like pins, bricks etc.) are put in a box permanently. I never miss one's hold. I takes me one to one and half hour to set it up. Because it takes me a lot of time on events I decided not to set it up again. During the next events I will show the Hitachi on the low loader truck. Another reason is that it's very risky to show a set up machine. I don't want to let it crash into the audience.
It's a very interesting machine to build. It really was a big challenge and I worked on it with lots of fun. When I saw the real machine for the first time I couldn't hardly wait to kick off. After more than three months of hard-working (during my studying period) it was ready. Allthough, later I changed the necessary because such a model is never finished.

Extensive description of the construction

As I've said earlier there's a large description of the model with lots of pictures on the website of Vroom. Unfortunately the text is only available in Dutch. Anyway, the pictures shows all phases. When I contact Vroom for some info about their new machine they immediate were very enthausiastic. They asked me if I could sent them pictures of the work in progress. They put the story and the pictures on there website.
The model has been changed technically in a meanwhile. In April 2001 I went to a model show for the first time with this Hitachi. It was, off course, the Modelshow Europe in Ochten NL. Right before the event the model was finished. I had hardly time to test it. The children's diseases where still in it and the months after I solved them all. Now most functions works very well and after solving all problems I took the machine outdoors for an extensive test.
In a news letter of Hitachi Japan there was also a small article about my model. Unfortunately my Japanese isn't very good. Maybe someone can translate it for me .....

Other data

Length:	149 cm
Width:	24 cm (extracted: 33.6 cm)
Height:	max. 3 metres
Length undercarriage:	47.5 cm
Construction:	???? many many hours
Date:	December 2000 / April 2001

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