Re-edition of the model of the Swedish MBT, built two years after the initial version. Features full suspension, remotely tilted hull, remotely controlled dozer blade and lights.

Datasheet:

Completion date: 06/03/2010
Power: electric (Power Functions)
Dimensions: length 67 studs (including main gun’s barrel) / width 25 studs / height 19 studs
Weight: 2.15 kg
Suspension: pendular bogies
Motors: 2 x PF Medium, 2 x PF XL

After almost exactly 2 years, I decided to re-build my perhaps most renown tank model. The S Tank, created back in 2008, has been extremely well welcomed, and no matter how many bigger, more accurate and more complex tank models I’ve built later, there were always some people claiming that S Tank was the best. I, on the other hand, was aware of many shortcomings of this model, and it was my goal to overcome these shortcomings in the following models – a fact that has apparently escaped the attention of many S Tank’s enthusiasts. Eventually, I decided to build this model again using my current level of modeling skills, even though it was against my ‘never build the same thing twice’ rule.

The original S Tank, or Stridsvagn 103, is a fascinating machine all by itself. Designed in 50s, it was the main tank of the Swedish army for the next 40 years, until arrival of the Leopard 2. What was the key of its success and its long-term service? The fact that it was designed with Sweden in mind. Moreover, it was designed specifically for defensive roles. This is why the typical turret was removed completely, because the tank was intended to stay hidden waiting for the enemy to come. To operate in difficult Swedish terrain, the tank was fitted with then-advanced hydropneumatic suspension and a turbine engine (in addition to a traditional diesel engine), making it the world’s first MBT to use turbine engine. Aiming was done by moving the entire tank, using the suspension to tilt the hull as needed. In order to fire its main gun, the tank had to be stopped and its suspension locked – it was clearly a drawback, but it was acceptable given the tank’s defensive role. It should be also noted that in 50s and 60s the fire control systems were relatively primitive, and tanks rarely fired while moving. Finally, the S Tank was equipped with a front dozer blade, which could be used to entrench it quickly and without the need for crew to leave the vehicle.

Thanks to removal of the turret, the tank’s front could be protected by a single armored plate, set at an angle that made it very difficult to penetrate. Actually, at the time it was designed, the S Tank’s front armor was virtually impenetrable for any other tank’s armament. To make a full use of this advantage, the crew included two drivers – the second driver was facing backwards and had his own set of steering instruments. Thus the S Tank was able to drive backwards quickly, while being protected from the enemy by its front armor, as well as being able to return fire at any time.

The S Tank was clearly an unorthodox design, so specific that Sweden remained its only operator, but it could be pretty lethal to any advancing force. Why? Because it had to be spotted before it could be engaged. Now, take a good look at a fully entrenched S Tank:

The new model of the S Tank was supposed to be: accurate, performing well and dark gray. I believe it meets all these conditions. The hull, which was tilted pneumatically in the previous version, is now controlled by linear actuators. It takes much more hull’s internal space, but the stability provided by such solution is peerless. Since my first S Tank was driven by a single XL motor, and the motor was apparently working pretty hard, and now the PF speed control is available, I used two XL motors, each one driving a single track. The tracks’ suspension system consists of 4 large, realistic road wheels (6595 wheels without tires work very well with tracks) suspended on pendular bogies, two wheels per a single bogie. I wanted to use a torsion bars suspension for the first time, but it was impossible to make it work together with the tilted hull. The front dozer blade is operated by a single PF Medium motor instead of pneumatics, and it works better than I expected (this is an application where pneumatics usually performs better than motors do). It should be noted that front part of teh hull houses a traditional battery box rather than the rechargeable battery, and there are two reasons for that. Firstly, a battery box can provide more power for two PF XLs used simultaneously, and secondly I needed something heavy in model’s front part to acquire the proper weight distribution.

As for the visual details of the model, my goal was to model the most distinctive ones. Like many tanks with long service period, the S Tank has undergone several modifications and there are 4 variants of this tank, which differ mainly in details. Few details are fictional, just to fill some empty spaces. Please note that this model uses custom chrome sprocket wheels, rather than original ones that come only in yellow or orange at the moment. These wheels have been purchased at this Bricklink store.

The model took a lot of work and a lot of extra shopping for parts, but I think it was worth it. For me, it is clearly my best-looking tank up to date. It seems that models in dark gray look particularly well on photographs, which is why I attempted to make a couple of macro-like shots, even though I only had a general purpose lenses (macro lenses are expensive beyond human reason). The model performed very well too – it was my fastest tank up to date, and its large road wheels made the suspension’s work spectacular to watch. I have enjoyed driving it over a wrinkled blanket more than I enjoyed driving any other tank under any other conditions. However, there’s a good chance that it would perform better with a torsion bars suspension.

Photos:

Video:

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It turns out my blog had a most unusual bug up until now: when you wanted to subscribe to it, you would be redirected to a Paypal page with a donation form. This was some really odd malfunction resulting from an influence the Paypal donation form apparently had on the subscriptions form. It could have created a false impression that I’m trying to use some dirty tricks to get a donation from you, and I sincerely apologize for that. The thing is, you can subscribe now. I decided to get rid of Paypal donations at all, but I want each donor who helped me so far to know that his/her involvement was deeply appreciated and used thoughtfully. So, once again, my sincere apologies to anyone who got the impression that I’m some sort of a trickster. Please do not hesitate to let me know if you spot anything working in a weird way on my blog again.

Model of a human arm. Features 4 electric and 4 pneumatic functions.

Datasheet:

Completion date: 28/02/2010
Power: electric (Power Functions) / pneumatic (fed from external pneumatic compressor with an airtank)
Dimensions:  unknown
Weight: unknown
Suspension: none
Motors: 3 x PF Medium, 1 x PF XL, 1 x RC

Just another weekend build – this is basically a late realization of an idea I had back when I was a kid. The goal was to build a model of an entire human arm, with palm included, that would have as much realistic functions as possible while being of more or less accurate size. The look of the arm was considered insignificant.

The most complex part of the arm is obviously the palm with 4 fingers and a thumb. The thumb can be bent and raised/lowered, whereas the remaining 4 fingers have two joints in each of them. The index finger was operated independently, and it was fairly possible to operate every finger individually, except that it would take two times more pneumatic hoses, which were already quite numerous (8 of these was going through the arm). The palm can be theoretically rotated through full 360 degrees, but I never actually tried it for the sake of the hoses in the wrist. The whole arm was heavy and a bending under its weight a bit, but it worked well. I think it was pretty satisfactory for something that was built in just two days.

Photos:

Video:

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Media reference:

Brick Tales, CrunchGear, Engaget, Fascinating LEGO Model Of The Day, Le Journal du Geek, NowhereElse, Switched, Tamasindo, The Geek Church, Tinkerology

Model of a JCB skid steer loader. Features drive, steering, remotely raised arm, tilted bucked and working roof lights.

Datasheet:

Completion date: 14/02/2010
Power: electric (Power Functions)
Dimensions:  length 31 studs / width 18 studs / height 20 studs
Weight: 0.73 kg
Suspension: none
Motors: 3 x PF Medium, 1 x micromotor

No a long ago, I have come into posession of the LEGO micromotor, something I wanted to have for years. Micromotors are unique, hard to get at a reasonable price, and impossible to replace in certain cases. When I finally got mine, I wanted to use it to control the horizontal angle of the main gun’s barrel in my T28 model, but the model was almost complete by the time I got the motor. Then it occurred to me that the smallest project on my list could definitely use the micromotor.

JCB 180 is a simple tracked skid steer loader. There are plenty of skid steer loaders and I was never interested in building one, viewing them as simple and technically boring. The JCB 180, however, is one of few loaders with a single arm instead of two, and that makes it challenging.

My goal was to  achieve maximum functionality while showing as little mechanics as possible. I’ve spent quite a while trying to fit a small transverse subtractor into the chassis, but I had to admit that it’s too large at this scale eventually. Therefore the drivetrain is very simple: it consists of two PF Medium motors, each driving a single track. Third PF Medium motor drives the linear actuator that controls the loader’s arm. Having one arm instead of two turned out to be a blessing in disguise, as there was no space inside the hull to drive two linear actuators or to transfer the movement from one arm to another. The roof lights are a good example of how compact this model is: they are coupled with the micromotor, because there was no space to connect them elsewhere.

The micromotor was located at the end of the arm, and it proved quite easy to integrate into a liftarms-based structure. It uses 3:1 gear reduction to change the bucket’s angle. I did some capacity tests with Lucius the hamster (roughly 60 grams heavy), and he was able to stay on the bucket without causing any sort of mechanical malfunction. The capacity, however, is severely limited by the fragile bucket’s construction – the first bucket I made was so heavy that it tilted to the side in a very ugly way. The final bucket was optimized for minimum weight.

The model was built in less than a single day, and it could certainly be somewhat upgraded. But I was satisfied with its functionality and look anyway, and considered it a relaxing build, without the need to make it better & better. It was also Lucius’ first time to appear in the AFOLs’ world.

Photos:

Video:

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Model of the American WW2 super heavy tank prototype. Features full suspension, drivetrain with a subtractor, lights and advanced main gun control system.

Datasheet:

Completion date: 13/02/2010
Power: electric (Power Functions)
Dimensions:  length 73 studs (including main gun’s barrel) / width 30 studs / height 16 studs (not including aerials)
Weight: 2.2 kg
Suspension: pendular bogies
Motors: 2 x PF Medium, 2 x PF XL

T28 was an unusual project. Started in Spring 1945, it was designed to break through German defenses and to counter German super heavy tanks such as Maus or E100 (none completed, fortunately). The designers focused on the armament and armour of the tank at the cost of its mobility, and they decided not to use a typical turret as it would not be needed against fortifications. T28 had one of the thickest tank armours in history, but it was driven by an V8 engine providing merely 500 HP – a very little power for a tank of such weight. It was also one of few tanks to move around on 4 tracks. The outer set of tracks could be removed for transportation by train. The tank could drive on a road on inner tracks, towing the outer ones behind.

Out of 25 planned T28s, only two were built. The war ended before they were operational, and in 1947 they were subjected to evaluation. It went bad – one prototype was completely destroyed by engine fire, and the other one proved that a 500 HP engine can barely move it. Both were supposed to be scrapped, but the undamaged one was found in 1974 in a back field at Fort Belvoir, Virginia. It is unknown where it was earlier, and it is unknown how a tank of this size can remain unnoticed inside a military base

The model is relatively simple on the technical side. It uses only 4 motors, two to drive and the other two to control the main gun. Just like in the real tank, the main gun has limited traverse and elevation. The drivetrain consists of a subtractor and two PF XL motors, one for drive and one for steering, on assumption that it takes quite a torque to steer a tank that wide and with 4 tracks. The model is not entirely accurate – one of departures include a V6 piston engine in the back, instead of fuel tanks. The real machine was driven by V8 engine, but only 6 pistons can be seen through a 8×8 grill, so I used a V6 engine. It has internal lighting, with lights pointed at each piston, and all the lights are coupled with the drive engine, so the faster tank goes, the brighter the engine is.

Another departure is the shape of the front of the hull. It was changed mainly to house the main gun control mechanism. The real tank had its gun mantlet attached to the hull, while the model’s mantlet is attached to the barrel and moves together with it, hence it needs a certain margin of free space around it.

The most challenging element of the model was its suspension system – not because it’s advanced, but because it’s so expanded. Each of the four tracks uses four pendular bogies, each with two road wheels. It sums up to the total of 16 bogies with 32 road wheels. Each track’s suspension is separate and independent, and each track consists of 123 tread links. Together with the spare track section on the armour, it sums up to over 500 tread links used for the model.

The model looked really well, and it definitely paid off to build it in dark grey instead black. It performed well, although the main gun’s barrel was a bit wobbly. It also seemed to experience problems with the drive motor – it could drive backwards and turn very well, but it seemed that driving forwards put more and more tension on the motor. The problem seemed to be getting worse over time, and it is possible that the PF XL motor used for drive was defective. Because of that, the model appeared very slow on the video, whereas given a properly functioning motor it should have been faster. Still, it was my first tank in dark grey, and came highly acclaimed for its look.

Photos:

Video:

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Model of a concept bike. Features full suspension, drive and lights but no steering.

Datasheet:

Completion date: 31/01/2010
Power: electric (Power Functions)
Dimensions:  length 44 studs / width 16 studs / height 16 studs
Weight: 0.73 kg
Suspension: full with shock absorbers, left and right wheels connected together
Motors: 1x PF Medium

I like unusual vehicles and I like bikes, so I got interested in Dodge’s crazy concept bike (4 wheels and a 500 HP engine) quite a time ago. I wanted to build smaller, not motorized version earlier, but I eventually focused on a medium-sized motorized model.

The goal was to make it driven remotely, with full suspension, and looking as accurate as possible. Steering turned out to be impossible – the real bike has left and right wheels suspended independently, and is steered by tilting left / right.  With the LEGO model, it became apparent that both front and rear suspension needs a solid axle connecting two wheels in order to maintain the proper stiffness. Since there was no place for another motor anyway, I decided to give up the steering completely.

The model was eventually not entirely accurate, but it maintained the size and the silhouette of the original vehicle.  All electric and almost all mechanic parts were covered up, the model was fitted with front and rear light and an integrated on/off switch. I liked its look and I consider it an interesting experiment, even though it was not so really  fun to drive only straight ahead

Photos:

Video:

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On January 28th, me and my fellow LUGPol member, have made our way into the Polish TV. And yes, we brought some bricks along.

At the end of January, the LUGPol community has been approached by one of the major regional Polish TV stations, TVN Warszawa, and asked for some members willing to take part in a short program on LEGO bricks. Two members agreed – me and a renown castle-builder, Paul Michalak, better known as Kris Kelvin. We were asked to bring some of our creations along, unfortunately we have only learned it a day earlier, so the only thing I could bring was the unfinished model of the T28 super heavy tank. And yes, I forgot to bring the PF remote along, so I could turn the model on, but nothing more

The whole program was broadcasted live and lasted for nearly 12 minutes. We managed not to pass out of stress, and to present our hobby to the public in a friendly manner. Below you can see the complete recording in two parts (I’m still restricted to 10 minutes per video length at YouTube, unfortunately). The recording is obviously in Polish, and there are no subtitles. I was trying to prepare some, but the amount of work required to translate 12 minutes of conversation and to embed it into the original video so that it stays synchronized proved to be devastating. It was not a really insightful conversation, as the editor had only brief idea of the AFOLs community, so you don’t lose much. Apart perhaps from a number of jokes, like e.g. when being asked about the costs of such a hobby, I answered that we’re both skinny for a reason

Videos:

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Small model of the iconic Peterbilt 359 truck, inspired by the HTC races organized by the DoubleBrick community. Features pendular rear suspension, openable bonnet, engine’s model and lights.

Datasheet:

Completion date: 14/01/2010
Power: electric (Power Functions)
Dimensions:  length 49 studs / width 13 studs / height 23 studs
Weight: 0.96 kg
Suspension: front: none / rear: pendular stabilized with rubber axle joiners
Motors: 1×71427, 2x PF Medium

This is a rare example of a construction inspired entirely by a competition specific for a given community. Namely, it was inspired by the Hard Truck Contest invented and successfully introduced by the DoubleBrick community. The exact description of the contest can be found via respective link, it suffices to say that the contest brings together small models of trucks (usually 14 studs wide), built with an accuracy and attention to details that make them a wonder to behold. I’ve spent some time watching the videos from the HTC races not to follow the course of the competition, but to simply enjoy the view of the beautiful models. I was hoping to get the builders from my country interested in similar races, and the best way to get their attention seemed to build a prototypical vehicle.

Having previously built model of the Kenworth W900, I have chosen another one of the most iconic American trucks, the legendary Peterbilt 359. When scaled accordingly to the size of the wheels used in HTC races, it turned out to be just 12 studs wide. The original HTC vehicles are 14 studs wide – I don’t know the reasons for which such a standard was accepted, perhaps it was simply more convenient or based on trucks with different wheels size, but I decided to take the challenge of building a 12 studs wide model. And it was quite a challenge – it was my goal to use identical wheels on all axles, which meant that I only had 6 studs of width available to make the front axle steered (original HTC trucks often use narrower front wheels).

As the idea of making the front axle suspended seemed mad, I focused on the rear axles’ suspension. Since the axles are based on the 5×7 open liftarm frames with differentials inside, it was natural to make them pendular. Concerned about the truck’s stability at high speeds, I have used rubber axle joiners as the suspension stabilizers – they were simply attached to the truck’s frame above the rear axles, and acted as shock absorbers whenever the suspension changed its angle. It should be noted that it’s an obvious solution to use some sort of a simple supporting structure between the frames of axle #2 and #3, but I wanted to model the original wheel span, and the model was simply too small to add an extra space for such a structure. It has slightly degraded its performance – the driveshaft connecting axles #2 and #3 is being pressed by the truck’s weight, and hence the truck is somewhat slowed down.

I have started to built this model with its both ends, separately with front and rear axles. It resulted in an uncommon frame design – the front half of the frame is purely brick-built, while the rear one is 100% liftarmic. Both halves are connected under the sleeper module, but the rear half lacks the stiffness typical for bricks.

The chassis design is pretty typical – both drive motors are located in front of the rear axles, and the steering motor is located behind the front one. Due to limited length of the chassis, I have used  a 71427 motor for steering. It’s located below, and partially inside the cabin, while the drive motors have been hidden under the mock-ups of the side fuel tanks. The final drivetrain’s gear ratio is 1:1.43.

Extra attention was given to the bonnet – I wanted it to be openable and to have a model of the engine underneath it, just like I’ve seen in the original HTC models, but I also wanted to take one more step and use PF lights in the headlights. It was eventually achieved by resizing the bonnet’s width from 7 to 6 studs. This is wrong in terms of the scale, but it makes the bonnet much more structurally solid.

I have deeply enjoyed building this model – perhaps partially because it took just roughly 4 days to complete. It was a valuable experience, showing that e.g. brick-built exterior may look pretty but is quite heavy – this is a really small model, but it weights almost 1 kg (just to give you a point of reference, 1 kg is a minimum required vehicle’s weight according to the rules of Polish Truck Trial). Still, it was reasonably fast and fun to play with, despite its pretty limited functionality.

Photos:

Video:

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New compressor design, using reciprocating motion instead of a rotary one. Smaller, stronger and more adjustable than traditional compressors, it can run up to 18 pumps.

I have presented some ideas for compressors earlier – they used at least two sets of alternatingly working pumps to keep the airflow fluent and the vibrations minimal. The problem, however, was that they all used a rotary motion to run the pumps, which made them large and structurally weak (e.g. because no central axle could be used to run the pumps, there had to be an empty space for the pumps to move). Both these problems increase rapidly with the growing number of pumps.

Having recently bought an extra supply of pumps, I was looking for a solution that would result in a compact and strong compressor. I have found it by replacing the traditional rotary motion by a reciprocating one. The compressor I’ve developed can use any even number of pumps between 2 and 18 (this limits results from the 12-studs long axle being the longest one we can use to put the pumps on), while being much smaller and stronger that the traditional ones. It can work with any motor, and has integrated gearing that can be adjusted to your needs by picking one of 4 available combinations. The only tradeoff is the fact that it generates more vibrations that the rotary compressors, but it still makes it a useful alternative. Even with 18 pumps, this compressor is only 14 studs long (not including the motor). The exemplary variant I’ve built for the video uses 8 pumps and its dimensions are just 9×6x7 studs (again, not including the motor).

You can find a complete instruction below, and the video is pretty explanatory. While many people tend to choose large compressor based on RC motors for large models, I dislike this solution because RC motors are noisy and difficult to use with the Power Functions system (they run at a current so high that it makes the battery boxes and batteries go off). Therefore for me, this solution will be a much better alternative in the future.

Photos:

Video:

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Pneumatic excavator with a full remote control. Features internal compressor, 3-position motorized pneumatic valves, integrated manometer, infinite freedom of superstructure rotation, lights, flashing warning lights, custom stickers and simple suspension.

Datasheet:

Completion date: 09/01/2010
Power: electric (Power Functions) / pneumatic (fed from internal electric compressor)
Dimensions (with arm in the transport position):  length 72 studs / width 27 studs / height 56 studs
Weight: 2.77 kg
Suspension:  pendular bogies
Motors: 7 x PF Medium, 1 x 71427
Pneumatics: three circuits with motorized 3-position valves fed from internal 4-pump compressor; integrated manometer

The idea behind this model was simple: to build a fully pneumatically operated excavator with a full remote control. Such a mixture is unique – there are many pneumatic models of excavators, but nearly all of them are connected to an external controller, which houses all pneumatic valves and usually also the compressor. I thought it would be quite a challenge to make a similar model fully remote-controlled, and I was sure that a pneumatically operated arm would look more realistic that one operated by linear actuators (as demonstrated by my earlier Liebherr R996 excavator model).

I was looking for a classic tracked excavator, and – somewhat tired of Caterpillars and Liebherrs – I turned my interest to the Volvo machines. The EC290C excavator scaled down accordingly to the width of the tracks seemed a most proper vehicle to model.

When you think of a pneumatically operated excavator, it quickly becomes obvious that it needs a possibility to return the valves to the neutral position, or – more simply – to close them. With such a possibility all sections of the arms could be controlled independently (well, almost – they would still affect each other by changing the air pressure in the pneumatic system); without it every section would have to reach its extreme position to let another one operate. Therefore I was looking for a small, simple way of controlling the valves, and what I found was an invention of my fellow LUGPol member, Dmac. It’s a very simple solution, but a tricky one – it depends on the elasticity of specific liftarms in relation to the internal gearing of a PF Medium motor.

I have assumed that with all valves controlled in that manner and fed from an internal compressor whose speed I can control remotely, I will have a full control over the excavator’s movement with a satisfactory degree of accuracy.

The model uses an uncommon chassis. It is held together by a single transverse beam which houses two PF medium motors inside it, along with a reinforcing frame made of liftarms. Thus the beam appears small and almost completely smooth, with the motors completely enclosed. It puts quite an extreme load on the beam’s components, but it results in a realistic look, as the real machine also has a single transverse beam in the chassis, and its drive motors are not visible, housed in the superstructure.

Another important thing is that the original Volvo excavator has its drivetrain fully enclosed within the tracks , with no parts protruding out at all. To model it, I have used two long sections of LEGO Technic chain, each connecting one drive wheel to the motor and remaining within the tracks at all times. The colour of the chains matches the colour of the chassis bearing structure, which makes them almost impossible to spot. Together with the enclosed motors, it has lead some viewers to ask how exactly is the whole model driven.

The construction of the hull may seem simple, but it was challenging. First of all the hull is flat but large, and it sits asymmetrically on the turntable. To keep it structurally solid, a supporting frame was needed – it was built around the turntable and integrated into the hull’s floor, taking 1 stud of its height. To make things more complicated, I have decided to use the newer turntable variant because it matched my needs better, but its width was odd while the hull’s width according to the scale was even. To compensate for this difference, a half-stud wide liftarms were used in the frame to give it an even width. There is an additional structure integrated into the frame right above the turntable, which holds together the base of the arm and the base of the pneumatic cylinders that raise its first section, as well as the motor used to rotate the superstructure. Additionally, the compressor was attached to the frame – firstly to minimize its vibrations and secondly to compensate for its height.

The construction of the rest of the hull is pretty traditional – there is a rechargeable battery at the back, serving as a counterweight, and motorized valves on the sides. The right front part of the hull houses the flashing lights mechanism activated by a lever inside the operator’s cabin, which controls four warning lights: two at the rear end of the hull, one on cabin’s top and one on the arm’s side. The cabin has a full interior, despite the fact that it’s slightly smaller (mainly in length) that its real counterpart.

The arm is relatively narrow – only 4 studs wide. It was built by blending two structures: bearing frame made of liftarms which holds it together, and the outer ’skin’ made of bricks which makes it stiff and gives it a realistic look. All the mounting points for the pneumatic cylinders are attached to the frame: the cylinders were integrated with the frame right at the beginning, in order to work out their optimal positions. There are three sets of pneumatic cylinders on the arm, two consisting of two cylinders, and one consisting of four. All of them are connected to the pneumatic system inside the hull: a mixture of elastic & rigid hoses is used to connect the pneumatic system to the arm. It should be noted that the sets of two cylinders tend to rotate around their longitudinal axle; to prevent this, they are connected to the arm by two axles that slide through certain points of the arm’s structure as the cylinders extend or retract.

The model worked well, given its strongly experimental construction. It has a number of significant flaws, however, the most important being the compressor which worked too slow. It was discovered only at the end of the building process, when the arm gained more weight that it had when the compressor was initially configured. The use of the manometer has paid off – the tests have shown that the pneumatic system was prone to breach at certain pressure. The turntable was a bit unstable, but it didn’t break – despite the fact that it had no supporting rollers or structure of any kind, and that at least 80% of the model’s weight was located in the superstructure.  There is a point on the video when you can hear the turntable squeaking as the superstructure rotates. The final drawback was the use of the standard bucket – I was planning to have a detachable custom bucket and some add-on devices to replace it with, and I even placed an extra outlet of the Power Functions system in the arm to let some motorized devices be connected and controlled. It turned out, however, that both the bucket and one add-on device I have prepared (a demolition jackhammer) were too heavy for the arm (the custom bucket was almost 5 times heavier that the standard one).

I was satisfied with this model despite its flaws. I had little experience with large pneumatic remote-controlled models before, and this proved to be a good lesson – especially when it comes to configuring the compressor. Usually, pneumatic models of this size use large compressors driven by the RC motors, which can fill the whole airtank in a couple of seconds. I had just four pumps and a compressor running at roughly 100 RPM, and it had to fill a system including over 3.5 meter of elastic hose (not including the rigid sections) and 19 pneumatic T-pieces.  Still, I was glad to have an unique self-contained pneumatic model with a fully wireless control. I liked its look to – the decision to use dark grey where I could theoretically use black as well has definitely paid off.

Photos:

Video:

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Media reference:

TechnicBRICKs