As many of you know, most of my LEGO creations are a blend of my childhood passions, notably Transformers, Nintendo, and uh, traffic lights? Yes folks, it's a little-known Baron von Brunk fact, but when I was a wee lad, I had an offbeat obsession with roadsigns, traffic signals, and road construction equipment. When others in my age group at the time were doodling pictures of Batman with crayons, I was drawing countless images of various road signs and orange construction cones. In fact, my mama used to snag roadcones from construction sites and give 'em to me as strange playthings. I dreamed of growing up and not only living in a house filled with LEGO bricks, Nintendo games, and Transformers figures, but also with authentic roadsigns and lights on the walls. That being said, as I've traditionally built LEGO Transformers or LEGO Zelda/Mario-related projects in the past, I decided to build a fully-functional (and near life-size) traffic signal lamp, constructed almost entirely from LEGO pieces -- sans the electrical wiring/lights! The actual traffic light itself is constructed from LEGO pieces (totaling about 1,700+), whilst only the wires, lights, power plug, and switch are non-LEGO -- with no other modifications, such as painting, glue, sanding, nor cutting.

This project is not an easy build to say the least, nor is it a cheap thing that you can slap together with random electrical parts. The LEGO construction was a heavily-modified project that went through a ton of revisions in both the 3D program LEGO Digital Designer, as well as in real life. As a result, the physical LEGO portion of this project via the LDD file may differ slightly than what you see in the final outcome, and if you attempt to build one yourself, you may notice a few differences.

The electrical system seems rather tricky, but is actually somewhat simple, if you have a basic understanding of soldering/wiring. The "brain" of the project is actually a model railroad traffic signal controller that I purchased on eBay, and then ultimately wired into the infrastructure of the traffic lamp. The light bulbs are pricey LED spotlights that use very little electrical power yet have a strong illuminated output. In simple terms, the LEGO structure serves as a house, inside the "house" are three spotlights each rigged up to a microchip which cycles through the colors like a real traffic light, and the front of the "house" uses a grid of colored transparent LEGO pieces which act similar to a Lite Brite set (or almost resembling a cluster of LEDs lit up). This "Lite Brite" system was covered in my popular Mosaic LEGO Lamps tutorial, which explains the principles behind colored light grids.

Like my other LEGO projects that I encourage fans to duplicate and make changes upon, this particular model can be altered according to your desire. You can forgo the whole electrical portion I've built and instead incorporate an Arduino system and control it via your computer. You can even mess with the colors or design, such as making the green light into a green arrow. It's all up to you.

Here are the following resources for parts:
  1. LEGO Digital Designer (free download) - 3D CAD program for making custom LEGO models - officially produced by LEGO Group, and not a third party program.
  2. My Traffic Light Signal LDD file (hosted on my site) - download the above program and import this model, which has its own 3D building guide included within. Here's a mirror link on my Google Drive. The instruction guide and parts list in an HTML format slideshow can be seen here.
  3. SuperBrightLEDs.com - a superb website for purchasing LED bulbs. The particular lights I used in my model can be found directly here - 48SMD-LED MR16, cool white, $9.95 each.  You'll need three of them if you plan on making a direct duplicate of my design. I would highly recommend getting the solid white 6,500K bulbs, as they have great brightness, as opposed to the red, amber, and green lights (of the same product), since they're sort of dull. If you purchase these lights, you'll need this specific type of base to house the bulb (you'll need three, of course). These particular bulb sockets have two small holes drilled into them, which are just the right clearance of being penetrated by a LEGO antenna or pin, which you'll see later when assembling the whole shebang.
  4. BrickLink.com - at this point I'll make the assumption that you're a highly skilled master LEGO craftsman, thus this link is pretty self-explanatory. For those of you out of the loop, Brick Link is a huge online "candy store" for new and used LEGO pieces. My LDD file for the traffic light contains a full list of parts; just to give you a fair warning, this project -- according the LDD file -- contains exactly 1,779 LEGO pieces. If you're a novice builder and lack the patience and ability to sit through assembling a titanic model of this caliber, I would not recommend trying this. Also keep in mind that more LEGO bricks also equals more spending. Albeit this structure is pretty straightforward and requires a lot of simple masonry and engineering techniques, as opposed to something crazy elaborate like my LEGO Nintendo 64 Transformer. The LEGO portion of this traffic light is basically one really big yellow box with a door on the back, to be blunt.
  5. Model Railroad Traffic Light Control Circuit - I personally chose a pre-assembled DC version of this item, to save time, and so that it could easily be modified to potentially become portable and run on batteries. The AC version is slightly more expensive but can use larger 120V light bulbs with a greater amperage rating. The DC version is cheaper, but is limited to smaller bulbs like LEDs -- hence why I chose them; also because lower-voltage bulbs tend to have lower output power and would have less a chance at melting my LEGO bricks. The DC controller required an AC adapter (12VDC output) to be spliced into the screw terminals you'll read about that on step 2).
  6. Radio Shack - you'll need the following things to mimic my design verbatim: on/off toggle switch, 22 or 20 gauge wire, soldering iron/gear, 12VDC output 120VAC input adapter, and small spade and ring terminals.
If you're capable of purchasing/downloading all of the above items, then proceed to obtaining the whole lot and then moving onto the next steps for information on assembly! Just to give you an estimate, you'll probably spend over $100 on one of these suckers; more than half of that is the electronic portion alone; I was lucky enough to have a bunch of old AC adapters in my closet, and the soldering iron, spade terminals, and wires were leftover from my giant LEGO NES controller. Again, this is not an easy nor cheap project to build, if you're unskilled with LEGO construction as well as basic electrical work. Some of the initial failures with lighting and LEGO construction may even seem rather frustrating.

I'll keep the assembly steps pretty straightforward, with some notes on the LEGO construction portion and a very basic schematic to go along with.

Step 1: LEGO Structure Assembly/Resources

  1. LDD Free Download
  2. LEGO Traffic Light LDD file hosted on my website (mirror link on Google Drive)
  3. LEGO Traffic Light 3D illustration and parts list slideshow in HTML format hosted on my site
Although my final project differs slightly than the 3D file in LEGO Digital Designer, if you follow this guide accurately, you'll be able to get the base model down flat. In the LDD file of this project, if you click on build guide mode on the top right corner, the program will generate a step-by-step guide for building the structure from the bottom to the top. You can click anywhere on the screen to move the image around, and of course play with the camera angles to zoom in and out of stuff for detail. This may seem a bit frustrating, hence I'm recommending that only skilled LEGO builders try this idea, as they'll most likely use their preexisting judgement to make improvements and repairs as necessary. To a novice LEGO builder, this will be very, very tedious. By the way, unlike LDRAW -- which is more sophisticated than LDD -- this program doesn't allow changing/re-ordering building steps: this means the program does its best to generate a linear build guide based on elevation, but often times you'll see random parts skipped or sometimes a piece left out and introduced later on -- notably in the first stage (green light) where bricks can appear at random spots -- such as the first few steps, which depict the green pieces floating in mid-air before going into the black Technic bricks. A skilled LEGO builder could spot an error like this and make judgmental changes when necessary; always make sure to go back and examine your work. This is a very tedious process that requires a lot of time, parts, and labor (and sometimes beer and Motörhead songs)!

As you progress throughout the stages of this tall structure, you'll notice something rather odd about the internal colors: the inside walls have black bricks lined against the yellow walls: this is intentional, and was a last-minute addition to the design. Initially, the walls were originally 1x1 thick, and because of their bright color they would allow light to escape from the inside. In other words, the light from the spotlights would peek through the yellow walls -- hence I've reinforced them with a second layer of 1x1 bricks, only black, so make the traffic light appear totally opaque from the outside when lit up. Also in my final design of the project, I've lined the walls with metallic reflective duct tape.

The rear door has Technic bricks interlocking with stud-on-side 1x1 bricks; at first I assumed I would lots of these to keep the door shut properly, but upon actually building this, I realized the seal was too tight, and when pulled apart, some of the internal parts could come loose. Feel free to omit a few of these "buttons" that keep the door shut.

On the rear door, there are three ports to hold the LED lamps. The grey Technic pins are to be slid through the back, so that the lamp bases can connect. The four holes on the bottom of the door are where the pins to keep microchip controller in place shall rest, and above one of the holes is a blank square area (a missing brick): this is intentional -- because this is where the power cord will go through. Towards the top of the door you'll see another deliberately empty area, albeit reinforced with modified bricks. If you purchase the exact same toggle switch I provided a link to earlier, you should be able to slide the switch through the hole snugly. Make sure to calmly twist the threaded plastic part of the switch when placing it through the hole, so that it goes the whole way back.

If assembled properly, your structure will be sturdy, the door will open and close easily, the colored areas on the front will have enough transparent dots to make a circular pattern, and the rear door will have sufficient infrastructure for keeping electrical components in place. Try not to be so detailed-oriented when following the LEGO instructions: yes, I'm telling you to not pay too much attention to the LEGO build guide -- because chances are you're better off using your own keen sense of judgement and LEGO-engineering to construct a sturdy building -- with only using the 3D LEGO instructions as more of an "inspiration" or suggestion. What really matters is that your tower is of the proper size requirements, maintains necessary components for keeping the electrical parts intact, and above all, actually resembles a traffic signal! Feel free to deviate with the design as you please, and even feel free to make any size changes. You can make the traffic signal bigger than the model I've built, and you can play around with the physical design. My model provided in the 3D instructions serves more as a basic suggestion of making a standard sturdy structure for a LEGO traffic light, with the bare necessities for eventually adding electrical parts -- and not necessarily intended to be copied verbatim (although you're obviously free to build it exactly the same as mine if you choose)! However, the only parts I'm encouraging to copy verbatim are of course the ports for housing the electrical parts, because if you decide to use my exact electrical parts list (lamps, microchip, and all), you'll need certain areas of the LEGO structure built in precision to maintain the electronics! In other words, details like the sloped LEGO pieces on the roof or the colors of the base aren't mandatory -- but things like placing the Technic bricks in the right spot to have the microchip held firmly are however mandatory (assuming you're using the same microchip as me)! If you plan on deviating with the electronic parts, like using your own schematic and circuits, then of course make sure to have the LEGO structure built to reflect your changes -- such as, for instance, making the bottom base larger and hollow for potentially housing an Arduino circuit.
Love it! LEGO-ise the world!
How do you come up with this epicness?!?
A lot of my blood, sweat, and tears go into these projects -- as well as money and beer.
Here's a traffic light in wpg, canada.
<p>You weren't the only one to have an unhealthy obsession with traffic lights and road signs.. I too had a room full of road signs and still dream of a working traffic light on my wall... Which just makes this project even more amazing.</p>
<p>Is there a way to import the BOM into BrickLink and have it figure out a way to buy all the bricks? Seems like it's going to take quite a while to source all 115 different bricks... You would think LEGO would make it convenient to buy the bricks out of their design software...</p>
Unfortunately, I believe LEGO Group removed the order function with uploading LDD models to their site -- so I also think that means you can't order an entire list of pieces directly from their catalog (I think). I'm more of a maverick, sloppy artist -- hence my process involves ordering a ton of pieces of a certain color that I've determined necessary (from Bricklink), then building my creation organically from the pile!
I am really impressed
I too shared your childhood obsession with all things having to do with construction. This brought back some good memories. Thanks for sharing!
Nice work, Baron. I think a couple of black ones of these (in Australia our traffic lights are black - pretty boring I know) will be making a presence at our next LEGO Fan Expo. Thanks for sharing the designs and all the tech details. Keep on building!
Thank you! Again, you can make your final design bigger or smaller or even a different color if you'd like, with my frame as more of a general suggestion. If the microchip I've used isn't sold internationally, you could also use an Adurino circuit and have several lamps rigged together!
Quite innovative indeed!
Myson loves trucks, stop signs, etc so it's not weird at all. My son likes this so I might be investing into some Legos soon. Nice work here!
Wow I could never do that probably because I'm very impatient

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Bio: Baron von Brunk: original creator of the LEGO/Transformers/Game Boy mashup - featured in Nintendo Power, CNN Geekout, Tokyopop, Discovery Channel Canada, Kotaku, Gizmodo, and ... More »
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