Sunday, August 30, 2009

Week TechVideo, 2009 #35 - Excavator with custom pneumatics

Pithivier57 is a French AFOL, who also decided to build a remotely controlled LEGO TECHNIC excavator. It is an 80 ton. CASE CX800 machine.

There are some PF motors on-board to move the undercarriage and rotate the cab, while the boom, dipper and bucket are operated by pneumatic cylinders.
On the remote unit there is a PF IR remote, to control the excavator undercarriage motors, and two additional PF M-motors for a compressor that feeds the model pneumatics, via a few umbilical pneumatic tubes.

Main point of interest of this excavator, are their unique and extra long pneumatic cylinders custom made by the author.
It is a characteristic from large size excavator TECHNIC models, to require long cylinders well above those produced by LEGO. While long ago some other builders have solved the problem of not having appropriate LEGO cylinders off-the-shelf, using ropes and dummy cylinders [1, 2], many others (LEGO inclusive [3]) have used the standard ones in a back-to-back setup to double their operative length. However, achieving this way a functional but quite unrealistic solution.
This is the point where some innovative minds, decide to go for customized solutions. And so Pithivier57 did also [4].

When I first saw this excavator videos, immediately remembered to have seen similar custom pneumatic cylinders before, made by someone else, somewhere...
After some searching got to find it again, at Jan Groen Brickshelf folder together with an explanation on how he did it. [5]

These seem to have been done in a very similar way, to what Pitihvier57 might have done too!?

There might be also a similar custom cylinders solution, on Anders Gaasedal's Volvo Excavator [6, see it also at TBs updated Excavators "Hall of Fame" post], but it is still not clear for me and I'm waiting on Anders' feedback on this subject.

Have meanwhile just realized , that Anders turned LEGO Designer in between [btw a TECHNIC designer (Goose Valley)], so it makes very unlikely to get an answer with further details about the cylinders. But on the other way it would make our chances to get a decent official TECHNIC Excavator with longer pneumatics in the future, somehow more likely...

Last Update: 2009.Sep.03 12:29 GMT

Main issue we can easily observe from Pithivier57's videos [7, 8, 9], are the cylinders sudden movements which may also look a bit unrealistic as it is the usage of pneumatic cylinders itself.
In fact this is an effect that may only get worse, as the longer the cylinders get.

In real life, such machines use hydraulic systems instead of pneumatic ones. They are a lot more powerful and work much smoother. However it is very unlikely that we ever come to see something similar by LEGO.
Thus one chance could be to play a bit with advanced pneumatic control solutions, that would allow to control the air flow into the cylinders and stopping the cylinders in the middle for digger action. Just like those developed by Mark Bellis years ago, and of course if there is any room left inside the model to accommodate it all.

As you may expect, several other photos from this CX800 excavator can be found at the author's BS folder too.

TBs TechNuggets 09 - Inside the PF Rechargeable Battery Box

Have you ever seen inside...?

Again Philo, took some photos from the new Power Functions Rechargeable Battery Box (8878).
Just take a look!

Just a few remarks,
  • Opening of the battery without significant damage, could be a bit tricky but not impossible as Philo have shown.
  • As expected we can see the battery includes internally, two 3,7V Li-Pol standard cells in series.
  • As it seems and as I guessed before, frustrating to see that TLG had available the required space to include some pin holes, in order help fixing this battery in studless buildings.
    Now we should use some modified plates with hole (probably the best solution), or similar.
  • Modifying the electronics board to override the 2h time-out function, seems now a vanished dream since all the control might be inside the Chip-on-Board circuitry (the black kind of a bubble in the PCB left side).
  • As a side note, I should say that against the approx. 4h charging time advertised within the leaflet coming together with the battery, I've measured it to be less than 2h 20', with the official LEGO 10V DC charger (8887).

Again as usual, you may also refer to the source at Philo's BS folder (not yet public at the time of this post).

Thanks Philippe!

TBs TechNuggets 08 - Inside the PF IR Speed Remote Control

Have you ever seen inside...?

Philo (who has some tendency to open things ) took some photos from the new Power Functions IR Speed Remote Control (8879).
Just take a look!

As usual, you may also refer to the source at Philo's BS folder.

TBs TechNostalgia 02 - 8448 alternative models Building Instructions

Imagine that if I speak about a TECHNIC Supercar or even mention 8448 (Super Street Sensation or Super Car Mk II), many of you will keep on your toes!...

Well, there has been some discussion at EuroBricks and also among some LEGO Ambassadors, about missing building instructions from old TECHNIC sets, namely the 8448 alternate models.
Some of those instructions used to be available for download through LEGO BIT application (Building Instruction Tool) but it is gone for the progress sake, now that PDF files turned into a standard.

The set comes with printed instructions for two cars as main models (a Convertible and a Gull Wing Doors).
There are also instructions for the mechanisms of 4 additional models, over the same chassis. However, the instructions for the bodies of these 4 models were not included and had to be downloaded from LEGO at the time. These have been nowadays, some of the most wanted instructions.

Eric (Blakbird) who had some years ago printed all them, answered the call and went into an huge taskforce to scan all those 66 pages with photo instructions.
After organizing them into 4 spearate PDF files (one for each of those alternate models), he made all available at his BS folder and told us via EB.

Thanks Eric!

Was also curious to find the same LEGO BIT instructions for 8458 (Silver Champion), third official model (Street Sensation). Again these were only available online long time ago and meanwhile lost.
Suddenly found them back from three sources and decide to add link here for Eric's copy.

Meanwhile found it should deserve a short note here too, and so I'm adding bellow the link for Nathanaël Kuipers (industrialdesigner) building instructions of a 4th unofficial model (Sportscar) exclusively made out of 8458 bricks.

This could perfectly had been another official model, or hadn't it been designed by Nathanaël.


Last Update: 2009.Sep.03 00:57 GMT

Single-set MOCs

Some people may think that, to create a MOC, one needs to have many parts, often hard-to-find ones. While this may be true for some of the great MOCs you see here on TBs , that doesn't necessarily mean you can't give wings to your imagination with only what's on the set you have recently purchased!

Just to give you an example, here are a few creations I found on Brickshelf. They are usually created from small or medium sets, perhaps because bigger sets are harder to have all (or at least the majority) of their parts reused on MOCs.

First and foremost here's a Jeep, made using parts from the 8256 Kart. DirkPV managed to create a new body shape while retaining the Kart's functionality (steering and piston engine), while at the same time adding working doors.

Next, there's a Truck Tractor, made by IcePicKPT using parts from the 8264 Hauler. Using all the set's wheels to make a rear double axis, as well as the attention dedicated to the front, makes this a quite realistic and serious-looking model.

Also, here's a MOC from mariner, who used the undercarriage from the 8294 Excavator and the rest of its pieces to build a Scissor Lift. One of the Linear Actuators lifts the "basket" to a considerable height, thanks to the number of straight beams this set contains. The ladder to reach the "basket" is a nice touch.

Again using parts from the 8294 Excavator, we have a Bulldozer created by Erik Leppen. In my personal opinion it is even better than the set's official B-model. There are even instructions on the respective Brickshelf folder!

Also, you might want to check out his One-Set MOCs folder for many other single-set creations of his.

From the 8292 Cherry Picker and inspired by a MOC by nico71, mrw created this Forklift. Notable is the fact that this MOC has four-wheel steering when the original set only has two-wheel steering. That's quite an achievement in ingenuity and improvisation.

Speaking of nico71, he created a great (not to mention proper; the official instructions only show how to built different attachments) alternative to the 8436 Truck, a Forest Tractor. Maybe the 8049 Forest Tractor with Crane will be something like this?

There are some other single-set MOCs at his folder worth checking out.

TECHNIC motorcycle sets don't usually offer much variation as to what B-model can be built using their parts, and the 8291 Dirt Bike is no exception. However, Co1Der managed to create something different with the parts, a Dragster. I especially liked the solution he came up with for the front wheels, where he used pulley wheels covered with Chain Links.

Due to their especially limited piece count and selection, entry-level sets offer quite a challenge for the imagination. That's why I admire grohl666's Monster Truck, built with parts from the 8290 Forklift. Not only the vehicle is quite different from the original, but also it has working suspension.

Like Erik Leppen, he has quite some more single-set MOCs (as well as other "regular" MOCs built with parts from multiple sets) on his folder, worth looking at. Among those is the one next on this article…

Finally, my personal favourite. This one is unlike anything I've ever seen, official set or MOC, and the fact that it was built using only parts from a single set, the 8294 Excavator, only gives it more value. Indeed, I've never seen a TECHNIC Parrot (or any other animal, for that matter) until I saw grohl666's Brickshelf folder. Not only it looks quite good, with Track Links covering empty areas on the body (another display of imagination), but it also has functionality: turning a knob on its back rotates its head, and via another knob on its butt (!) its wings flap. Truly brilliant!

I searched Brickshelf for quite a few sets, and these are what I found. It's interesting to see that the 8294 Excavator, last year's favourite set because of its versatility and selection of parts, was the one most used for single-set MOCs!

I'm pretty sure many of you TBs readers have also, on some occasion, bought some set, assembled its main model and perhaps the B-model, and then disassembled it and invented something with its parts. At least I have done it a few times in the past, only didn't document them. Want to share it with us? Then feel free to leave a comment with it! Thumbs Up

Saturday, August 29, 2009

TBs TechTips 25 - Connecting the PF Receiver to 9V (II)

One PFS design "flaw" (intentional or not), made it impossible to connect the PF IR Receiver to any old 9V source by simple using any of the PF Extension Wires (8886, 8871).
Thus several workarounds have been proposed and this was already discussed here at TBs before [1, 2]. From powering the IR Receiver from one of its outputs, to use an empty PB battery box there is always a solution that most fits your needs.

However these days while preparing a post still to come, I found the most compact workaround and probably the most interesting one. I've seen it being used in a mini tank MOC [3*, 4], by Jaeho Jung from BrickInside (the largest LUG in South Korea).

According to Jaeho Jung, this is a method developed by Minshik Kong, aka Sarafiel [5, 6] (another BrickInside member). The method explanation itself, can be found here* (you should be able to recognize the first video there ).

In simple words, the method consists of using a thin aluminum foil to short-circuit the 9V/C1 and 0V/C2 pins on the PF lead that connects with the legacy 9V source, via any 9V/PF adapter/extension cable.

I'm sure the images below, from Philo's 'Power Functions™ Presentation' webpage, will help you to understand the principles behind this idea.

Simple, brilliant and no bulky or limiting solutions, I would say!

*) All the links with reviews and uses of this method, are written in Korean but hopefully the photos seapk by themselves.

Related Posts Plugin for WordPress, Blogger...

© 2007-2014 TechnicBRICKs
TechnicBRICKs contents may be sporadically updated, if the authors finds further relevant info about a certain post, or content/spell mistakes. Hence please don't be surprised if you find few changes at later visits, relative to a previous read.

TechnicBRICKs often shows other peoples' creations and/or images. We always try to credit the author(s) and link to their main publishing website, and if possible with their name in real life.
Since this is not always possible, we request that if you find something here that is yours or from someone you know, you leave a comment on the respective post and claim the authorship.

TechnicBRICKs is optimized for Firefox 16.0 and 1600x1200 resolution displays or wider.

LEGO® is a trademark of The LEGO Group of companies which does not sponsor, authorize or endorse this blog.
LEGO, the LEGO logo, the Brick and Knob configurations, the Minifigure and MINDSTORMS, are registered trademarks of The LEGO Group.
Original LEGO images are copyrighted by The LEGO Group and are used here in accordance with their fair play policy.
You can visit the official LEGO® website at