8479 Barcode Dump Truck

[Blakbird]

As many of you know, I am trying to add as many LDraw models of Technic sets as possible to my Technicopedia. To date, I have included files for about 90% of the sets from 1977-1995. The LDraw files are useful for making computer renders, for making revolving animations, and for making images to demonstrate the functions. Some of these files were found on the Internet, some were donated to me by various helpful people, and some I've created myself. My Technic Brickshelf folder shows renders of all the sets which have LDraw files so far, almost 200 renders of over 100 models.

I was lucky enough to find models for some of the larger iconic sets like 8880 and 8480, but the really big sets are a huge challenge to build virtually and not many have attempted it. The first large model I tackled was 8862 followed by 8868.

Now I've moved on to an even bigger challenge, the dump truck from set 8479. I managed to build it over the course of 2 arduous days, and I thought I would share some of my steps here. Each of the renders you see took between 1 and 6 hours to run. You can find larger versions of all of them on my Brickshelf account (once moderated).

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I started with the last part of the instructions for some reason, the dumping bed. I decided that this was a large chunk of structure which I could do fairly quickly and would easily identify the set. It is made of 4 submodels: the base, the front panel, the side panels, and the tail gate. I only made one side panel and mirrored the other one using a transformation matrix.

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The next picture shows the beginning of the chassis. The differential is in along with the gears that lead to the optional motor (top of image). The other set of gears leading to a bevel will go to the Code Pilot to tell it how fast the wheels are turning. This speed will change the pitch of the engine sound the Code Pilot makes. You can also see the steering arms.

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Now you can see the steering rack and the links which give the steering Ackerman correction. The gearbox up front allows the steering wheel in the cabin to follow along with the HOG steering. The levers on either side are used BOTH to move the cam which actuates the touch sensor AND to move the pole reverser which will switch the transmission simultaneously.

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Big changes here. The rear pendular axle has been added. Interestingly, the rear axles floats freely longitudinally and, since there are no springs, it doesn't support any of the chassis weight at all. You can see the driving gears for the transmission and the many spur gears which lead back to the link which drives the bed. All of the gears are clocked so the teeth line up correctly. I hate it when virtual models have the teeth interfering. I make each axle assembly a submodel so I can rotate it as a group. There are over 50 total submodels in this file. You can also now see the front wheel wells. On the back end, notice how there are 3L axles with stud sticking out of the liftarms. These will support the bed. They are grouped with the liftarms so they will be rotated into the correct orientation to fit in the axle holes.

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This is the same as the above render but I've included the bed which I built earlier just to see how it all looks.

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Now I've added another layer of structure including the rear wheel wells and the gearing which leads to the front lifting arm mechanism. The structure looks pretty solid at this point.

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At this point I realized that I had completed all the mechanical functions, so I decided to strip away the structure and only show the gear submodels. This makes a pretty cool picture, but I screwed up the aspect ratio of the render so it is slightly squished vertically.

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Amazing how complete it looks when you add the wheels. As with all my models, always show the front wheels slightly turned. The model looks much more realistic and less like a computer model when everything is not perfectly square. Here I've added the vertical assemblies which will support the Code Pilot, the wheels, and the steering wheel.

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I hid the wheels and bed since they make it hard to see what I'm working on. The cabin is almost half done now. The angles on the front end were done with submodels. The angled sections are rotated about a custom rotation center coincident with the hinges. I rotate them until they line up with the front piece which I centered. I use 0.25 degree increments to get it just right. When the angled section was just right, I tried to mirror it on the other side but it didn't work because the hinge pieces are different left and right. This meant that rather than mirroring I needed to use the same submodel but rotated into an opposite angle.

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Almost done. The funny angles of the window posts were a challenge. The exhaust stacks are identical and mirrored. At first glance it looks done until you realize the whole lifting arm is missing.

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The lifting arm is the hardest part because of all the angle connectors. MLCAD does not line things up automatically, which means I have to do it all manually. The method I've developed for doing this involves first assembling everything in a single plane as shown in the image. The parts downstream of each angle connector are in separate building steps. I start by putting the rotation center at the middle of the first #3 angle connector. Then I select every step downstream of that and rotate 22.5 degrees in the X axis. This makes things line up perfectly. I continue the same procedure for each subsequent connector.

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When that process is done, I have this. It looks much better! I also added LSynth flexible hoses. I didn't bother putting flex cables inside since you can't see them and they consume a lot of file space. Getting the flexible parts just right takes a lot of time, but I think you'll agree that the result is worth it.

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Here's the completed lifting arm. I mirrored the arm side you saw above. The "claw head" is another submodel. Each individual claw is a submodel of that, and they are also mirrored. The ball connector had to be rotated to a very precise compound angle to point at the flex tube. I synthesized the end of the flex cable only (the visible portion). I couldn't bring myself to spend the time to synthesize the electrical wires though. Perhaps someone else has that kind of patience.

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1300 pieces later, and here's the current final image. I haven't placed a background or floor in it yet. You can see that I even included the spare tires in the bed. As usual, I put them at interesting "random" angles. All the tires use the rubber color (256) instead of black (0) because it looks better rendered. I think it turned out pretty well, but there is one major flaw in the model still. Can you tell what it is?

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After all that, I'd be happy to answer any questions. And no, I don't know which model I'm going to do next.

Edited September 15, 2010 by Blakbird

[DLuders]

Wow! The renders are fantastic! I don't think that the "box art" on TLG's original 8479 set were as good as yours.

When you mentioned that there was a "major flaw" in your final render, I'm trying to compare it with Brickfactory's 8479 Instruction Page 52 to spot the differences:

(1) The "Code Pilot" sticker is missing from on top of the cab.

(2) The shape & size of the Battery Box behind the cab is different.

(3) There is a small cable running from the battery box that isn't shown on your render.

[Zerobricks]

Great renders! Oh and a small error I see, the 9 V geared motor sits too low in your model.

[Blakbird]

Wow! The renders are fantastic! I don't think that the "box art" on TLG's original 8479 set were as good as yours.

Thanks! That's quite a compliment.

When you mentioned that there was a "major flaw" in your final render, I'm trying to compare it with Brickfactory's 8479 Instruction Page 52 to spot the differences:

(1) The "Code Pilot" sticker is missing from on top of the cab.

(2) The shape & size of the Battery Box behind the cab is different.

(3) There is a small cable running from the battery box that isn't shown on your render.

1. I don't have any of the stickers in the model since they don't exist in LDraw. That includes the "Code Pilot" sticker on the top, the headlights, tail lights, and instrument panels.
2. That was it! There is no Code Pilot model in LDraw so I had to use the Mindstorms Scout. You don't notice the difference much from this angle, but it definitely wrong. Luckily for me, Philo is in the process of making a model for the real Code Pilot right now!
3. True, I didn't do the electrical wires. The wire running down to the touch sensor on the claw isn't there either.

Great renders! Oh and a small error I see, the 9 V geared motor sits too low in your model.

I actually hadn't noticed that. Thanks for pointing it out. I'll fix it.

Edit: I went back and checked and my model is actually correct. That suggests that either the instructions are not accurate or the LDraw model of the motor is not accurate. Since my model is not built right now, to figure it out I checked Brickshelf. The image below suggests that there really is a gap above the motor and therefore the instructions are wrong. On the other hand, if you look closely, you'll see that this guy installed his Code Pilot upside down!!

Edited September 15, 2010 by Blakbird

[allanp]

WOWWEEE these are some great renders. I especially like the one of just the mechanisms with the rest stripped away

[CP5670]

These renders look great and show various stages of the construction nicely. About how many hours did it take you in total?

You might want to try SR3D Builder instead of MLCad for some sections though, especially for those odd angles used on the cab and claw arm. The interface is a bit clumsy and takes some getting used to, but its connection-based brick placement is especially useful for Technic construction.

Edit: I went back and checked and my model is actually correct. That suggests that either the instructions are not accurate or the LDraw model of the motor is not accurate. Since my model is not built right now, to figure it out I checked Brickshelf. The image below suggests that there really is a gap above the motor and therefore the instructions are wrong.

There is a two-plate gap above the motor on mine. You're meant to be able to slide out the motor (after removing the 1x1 round plate) and put it in the other side, so the truck can be driven by it. Do the instructions show it differently somewhere?

[phool]

OMG, that is one sexy final render

Edit: May as well mention that this black & green colour scheme is one of my favorites. In fact I just picked up a copy of the fibre-optics multi-set just because I liked the look of the hovercraft-boat-thingy with this colour scheme so much.

Edited September 16, 2010 by phool

[Conchas]

The renders are indeed superb! As usual Eric.

The motor lays in fact at the position you represented. It must because it must get in and out, as the motor position is interchangeable in this model.

Simply one of my favorite Technic models ever!

It offers great levels of playability and fun.

[Plastic Nurak]

Good job, Eric :) .

EDIT: I was giving you false hopes about a rendering made by me.

Edited September 16, 2010 by Plastic Nurak

[zyrex]

Great renders and great job!

...I think I have to tear my 8479 down and rebuild it, this brought back many memories ^^

[Milan]

Incredible renders, as always.

Can someone explains a little bit how the Code Pilot works?

I have seen 8479 on YouTube when the truck is moved in different speed, sound of the engine is changed as well, and when truck stops, you can hear air brakes, and when claw is operating, engine works fast.

I like that very much.

[Blakbird]

Can someone explains a little bit how the Code Pilot works?

I have seen 8479 on YouTube when the truck is moved in different speed, sound of the engine is changed as well, and when truck stops, you can hear air brakes, and when claw is operating, engine works fast.

I like that very much.

Since it came out in 1997, you'll be able to read about it in Technicopedia soon enough!

The Code Pilot is basically a precursor to the RCX. It is a computer control with one connection for a touch sensor (switch) and one motor output. It holds 6 AA batteries (9V). There is no computer input for programming, instead you program it using a large sheet of bar codes. There are motor directions, durations, sounds, and other things on this sheet. The Code Pilot has a red light and sensor which it uses to read the bar codes. The sensor also "watches" a gear wheel driven by the differential so that the engine sound changes with the vehicle speed (3 speeds total). The brake sounds and "hydraulic" sounds of the engine going faster are part of the preprogrammed option for the dump truck. They are activated when you move the switch to engage the claw or the dumping bed; they are not automatic with speed.

[Munkay]

Wow. Incredible! Like others have siad, your rendering looks beeter than Legos on the factory box! One question concerning the model...

IS the rear axle "free floating" You mentioned there's no springs in the rear and it apears there is no solid conection to the chassis, with only a rear pivot point for a make shift suspension. Thanks!

[Blakbird]

Wow. Incredible! Like others have siad, your rendering looks beeter than Legos on the factory box! One question concerning the model...

IS the rear axle "free floating" You mentioned there's no springs in the rear and it apears there is no solid conection to the chassis, with only a rear pivot point for a make shift suspension. Thanks!

Yes, the rear axle is free floating. It does not support any weight. You could add some springs and change that though.

[Rijkvv]

Since it came out in 1997, you'll be able to read about it in Technicopedia soon enough!

Does this mean Technicopedia gets the 1996 update in the near future?

Amazing rendering Eric. When I built mine, I made a mistake and placed an electric wire connector one stud wrong. Result: the inner gears were blocked, and to fix the problem I had to take half of the model apart. Well, that's why you need to check the moving parts during building, but it shows the complexity of this set. To create such a model, and to align all gears properly... respect.