Imperial Journey

With the MegaTree fully functional the last stage of the build is to move the controller and power supply from the breadboard to its final location (hopefully not its final resting place) in a waterproof outdoor box.

For this I chose a steel NEMA 16″x16″x6″ enclosure. Waterproof, lockable, and built like a tank. Total overkill, but found one on Amazon for $50. If I decide to go larger in the future this box has enough room for two power supplies and two or three controllers plus cable management.

One of the nice things about NEMA boxes is that they have a removable steel plate that you can take out to mount things on – this makes the job much easier!

One of the additions to the final packaging is to connect all external wiring through terminal strips. This makes the system more robust and reliable by isolating the more delicate controller and power supply connectors from the heavier cables. All external cables are connected through waterproof glands providing extra protection.

The MegaTree is sitting in the workshop ready to go when we put up Christmas decorations, typically just after Thanksgiving.

Individual LEDs don’t need much power. Hundreds of LEDs need quite a bit of power. The MegaTree now has 8 strips with 50 LEDs each for a total of 400. Each of these LEDs will consume about 1/3 of a watt of power at full brightness. So 400 of them will use around 130 watts. The 200 watt power supply can easily handle this. The WS2811 strings use 5 volt power resulting in 27 amps going down the wire. The LED strings are made with thin wire which causes massive voltage loss. Somewhere around 200 or so LEDs the voltage drops too low and the LEDs don’t work. The LED controller also becomes overloaded and won’t drive this many pixels.

WS2811 LEDs use three wires: +5V, ground, and data. They are designed so that data is regenerated at each individual LED and works up to the addressable limit of each controller, typically 1,000-2.000 LEDs per controller.

Long strings work by connecting additional +5V and ground wires to the string every 50 to 100 LEDs – power injection.

Standard WS2811 strings have pigtails for power injection on each string making it simple.

I ordered the same pixel string with waterproof connectors expecting them to also include power injection pigtails. Get ready to hook up the new strings and nope, just a three pin female waterproof connector on one end and a three pin waterproof male connector on the other end.

Ok, no problem. The pixel strings are spaced too far apart at the bottom of the tree so I need extension cables. I will just make extension cables with power injection. This will give me power injection every 100 pixels which is fine.

Order a set of 3 pin waterproof connectors. Too small. Check the connector details more closely. OK, there are small and large connectors available. Order a set of large 3 pin waterproof connectors. Hmmm, the large connectors don’t fit either…

Dig out the calipers, carefully measure the connectors on the pixel string, go through multiple listings on Amazon, and order a set of connectors that look like the right dimensions. They don’t fit either. Krud! What is going on here?!?

It looks like the Rextin WS2811 pixel string with waterproof connectors is using a custom connector that isn’t readily available.

Why am I not surprised? Well, each pixel string has a waterproof connector that does work. And I have wire cutters and no sense of self preservation! Cut off the connector, splice in an extension, and add the power injection to the extension. Use a standard 2 pin waterproof connector with the extension and make a custom power injection cable that also uses standard 2 pin waterproof connections.

Do this with every other string and you have a set of pixel strings with power injection and the proper spacing for the bottom of the tree. String them up and viola! the tree is done!

Connect the WLED controller to the first string, connect the custom power injection cable to the power supply and the rest of the pixel strings and power it up.

Fire up the laptop, connect to the WLED controller, enter the settings for the 8 strings on the mega tree, and hit go.

Lights! And there was much rejoicing!

Go through the various lighting effects that are available on WLED. Choose a dozen that look good. Arrange them into a playlist. Make this playlist the default. Power cycle the WLED controller. Stand back and watch a MegaTree in operation!

And there was MUCH rejoicing!

The LED strings need to be attached at the top and the bottom of the tree. The MegaTree companies make what they call Toppers – round plates with holes around the edges. These are available for $40-$50.

As you may be aware I have a junior grade machine shop. And a bunch of steel I haven’t done much with. Dig through the pile and drag out different sizes of discs.

I had my choice of 8″ x 1/4″, 7″ x 3/8″, or 4-5/8″ x 1/4″ steel discs. All complete and massive overkill for this use. The 4-5/8″ diameter disc it is!

The main job is to drill 32 evenly spaced holes around the edge. To make even I fired up a drawing package on the computer, drew outer and inner circles, and added a series of radial lines at 11.25 degree intervals. Cut out the circle, glue it to the steel disk, and center punch the intersections to get ready for drilling.

To make sure that the hole spacing was even and comfort my fear of flying parts I made a simple fixture and bolted to the drill press.

A piece of 1/2″ EMT is being used as the “trunk” of the tree. Head over to the lathe and turn down a two inch long chunk of steel rod to just fit. Drill it, tap it, and bolt it to the disk. Hit it with a couple of coats of paint and Viola! A finished topper!

The tree base “should” have been the most straightforward part of the job. Get some PVC pipe, bend it in a four foot diameter circle with four T connectors for legs to the center, and done. I’ve used this approach for holding up boat covers in the past and it works great.

3/4″ PVC pipe should be perfect for both strength and flexibility. Hmm, it doesn’t want to bend. No problem – hit it with a heat gun to warm it up and then bend it. Which meant that it was now both collapsing and cracking.

Looks like I got the wrong stuff. Let’s try this again with CPVC supply line instead of PVC waste and vent line.

The 3/4″ CPVC didn’t crack or collapse, but it just wouldn’t bend into a four foot circle and stay in the T connections. After fighting this for several hours I finally gave up and moved on to the 1/2″ CPVC I had purchased just in case the 3/4″ didn’t work.

I finally managed to make a base out of the 1/2″ CPVC. But I’m not happy with it. It will work for this year and I will figure out how to build a better one next year.

Looking back at it,previous projects with this type of tubing were partial circles, not full circles. They had a larger radius. And used longer sections of tubing between connectors. This part of the project was much harder than it should have been. Live and learn…

Assemble the base, trunk, and topper and add the LED strings. The LEDs were attached to the topper with nylon ties and to the base with a combination of nylon ties and bungee cords. The height of the trunk was determined by connecting the first string, moving the topper up the trunk until it was at a good height, and then marking and cutting the trunk.

Adjust all eight strings around the base so that they were evenly spaced and get ready to fire up this tree!

The tree itself is pretty simple – a set of vertical strings of LEDs tapering in at the top to look like a Christmas tree.

LED strings and strips come in 15 meter (15-1/2 ft) lengths. The standard for strings is 50 LEDs wired together – this actually looks like traditional Christmas tree lights. Since this is for outdoor use it is a good idea to go with waterproof connectors. The test string I originally ordered came with interior connectors (foreshadowing).

Since the tree is still experimental I’m starting with a small tree, one around six or seven feet tall. I also decided to build a half circle tree since most people will only see it from one side. I decided to go with a design of 8 strings of lights for a half circle, 16 strings for a full circle. By building a small tree I can use a single strand of lights going both up and down, thus only needing to buy 4 strings of lights.

Surprisingly there aren’t that many choices for LED strings with waterproof connectors. I ended up with Rextin WS2811 strings.

You don’t just hang the lights from the tree. To ensure consistent spacing they make strips of heavy plastic that you plug the lights into. These strips have holes every inch allowing you to space lights two inches, three inches, four inches, or whatever you want. These mounting strips mechanically support the individual LEDs keeping strain off of the wiring – a good idea when you have long strings that may experience wind and snow loads.

It looks like this is a specialty item. While it is available from multiple sources they are identical – only 150 foot rolls and all vendors are exactly the same price. Whatever.

The first phase of construction is to cut a piece of the mounting strip to length and then stuff each individual LED into a hole in the mounting strip. A thick, heavy, strong mounting strip. The companies providing MegaTree kits have a special block to simplify this process. Being (relatively) cheap I discovered that a 9/16″ hole in a piece of 2×4 works well.

I had carefully designed the tree based on spacing the lights at three inch intervals. This makes a relatively inexpensive starter tree. Stuffing the LEDs into the mounting strip revealed that the wires were just a bit too short for three inch spacing – they could almost be pulled into place but with considerable strain. Krud!

After futzing around with the LEDs and the mounting strip I finally internalized that the initial design wouldn’t work. Back to the drawing board! Using two inch spacing with a full strand of lights for each vertical run would give me a roughly nine foot tall tree. And require twice as many lights…

Which wasn’t a complete disaster. Twice as many lights means four more strands. At roughly $15 per strand this still wasn’t too bad. Time to place another order.

While the K1000-X controller was fully functional the software development environment didn’t come with the packaged effects I wanted. It provided the tools to develop them, but didn’t include the ones I wanted.

There was an effects package available, but it cost. It wasn’t very expensive, but wasn’t widely available, didn’t have reviews, and I was reluctant to enter my credit card information on a web site I already considered somewhat sketchy.

I actually bought two controllers: the K-1000C and a simpler controller that supported the Open Source WLED software package. Specifically, the Aromfentu WLED Controller ESP32. There are many controllers like this available so this was a somewhat random choice.

WLED runs on an Arduino microcontroller. My initial thought was to get an Arduino development kit, learn how to program an Arduino and WLED, get the lighting effects I wanted, and finally transfer a completed program to the production WLED controller.

I started with the K1000-C controller because it looked like it was easier to transfer lighting effect programs to it – develop a lighting program on the PC, copy it to an SD card, and plug the SD card into the K1000-C. And it actually proved that easy. On the other hand, it looked like programming the Arduino would involve re-flashing the software onto the microcontroller – a much more involved process.

As I looked more closely at the Aromfentu WLED controller I discovered that it had a WiFi interface. And a built in webserver. With complete control of lighting effects. And about 100 included effects. Not to mention multiple instructions and tutorials available. This requires closer investigation!

Connect the WLED controller to the 8×32 panel – we are looking for 2D capabilities. Drag out a laptop with WiFi. Power up the WLED and check the laptop. Hmm, there is a new WiFi access point showing up, just like the instructions claim. Connect the laptop to this access point and in does, indeed, connect. Following the instructions point my browser to IP 4.3.2.1 and bingo, I’m in the WLED control panel!

At this point they really want you to connect the WLED controller to your local WiFi network and put it on the network (and the Internet). But you don’t have to, you can continue accessing it as a local device. Which I did since I don’t like to have dumb devices like this exposed on the Internet.

Once in the WLED control panel I lit up the 8×32 LED panel and started poking though the effects library. Wow – just what I was looking for! Some of the effects were meh, many were OK, and several were “I rather like that one”. Some more poking, Interneting, and experimenting and I had a set of nice effects running in a loop. Power the controller up and it runs the effects loop until you turn it off. And there was much rejoicing!

With all of the individual pieces working it was time to build the actual tree!

With the (first order) of parts on hand it was time to blow something up! The actual intention was to see if I could connect the power supply, controller, and an LED string and blink the lights, but I have a history of success in connecting electronic devices in a way that lets out the magic smoke…

One of the first discoveries is that there are almost no instructions included with these random parts. The few instructions that are included are confusing, incomplete, and appear to be a Google translation from another language. Apparently using an old version of Google translate.

No problem! Set up my electronics workbench (also known as clearing off a spot on my desk) and get to work. Step one was to wire everything together and plug it in.

Nothing. OK, go over the “instructions” again, hit the Internet, and cruise YouTube. Turns out that I didn’t understand which three outputs of the 8 available on the controller should be used.

Connect the wires according to the new knowledge and the LEDs light up. Cycle through the presets on the controller and various colors flash away. Success on step one!

Since various devices were going to be connected and disconnected repeatedly the very next thing was to find a small piece of plywood and bolt the power supply and controller to it. And clamp the power cord to the plywood so that I wouldn’t damage the delicate terminals on the power supply. This made it much easier to move the test rig around and to change things. I quickly learned that plugging and unplugging the power cord to turn it on and off was a nuisance and added a power switch to the breadboard.

With the hardware basics done it was time to tackle the hard part – software!

The K1000-C controller was selected because it has an editing package for developing lighting effects. Unfortunately the software package included with the controller wouldn’t install. A bit of research uncovered the website to download the latest version.

This website felt sketchy to me. I’m somewhat paranoid about installing and running unknown software and this just made me nervous. Fortunately I have more than one PC available! Dig out an old machine I didn’t especially care about and install the software on that.

This time the software installed. And ran. And looked like something out of the 1990’s. Distinctly primitive looking. But a reasonable set of capabilities.

After a few hours of research, YouTube, poking around, exploring 17 approaches that don’t work, and digging through several desk drawers to find an SD Card I finally had my first program. And it worked!

Deciding to go for broke I hooked up the 8×32 LED panel and studied the instructions for scrolling text. An hour or so later I had “Test” scrolling across the panel! OK, let’s see if we can really master this. A few minutes later I had the joy of watching “Test Red Green Blue” scrolling – with the text in white, red, green, and blue.

On that high note I turned everything off and walked away for the day.

In yet another cycle of how I learn something new, start with something really simple and try to make my early mistakes as cheaply as possible. Since all of the parts are readily available, head down to the local hardware store and load up a basket full of Mega Tree guts.

Yeah, right. In the real world there are two choices: go with a supplier of Mega Trees and components like Holiday Coro or Boscoyo Studio. Or get a bunch of cheap components straight out of the Far East and build everything from scratch.

Not a difficult decision. Fire up Amazon and prepare to be confused by all of the choices! Recall that I need power, controller, and lights.

The first major decision is what voltage to use – this drives every component in the system: 5V is easiest to work with but limited for long runs of lights. 12V is best for longer runs but is a bit more complicated to work with. 24V is for professional use. 5V it is!

With several hundred LEDs planned I will need a fair amount of power. That looks like at least a 200 watt power supply. Throw a BTF Lighting 200 watt 5V power supply in the cart.

The lighting controller is the heart of the system. This is where I’ll need to do most of the experimenting and learning. Proven controller packages for Mega Trees run several hundred dollars. After going around in circles (something I’m really good at) I finally decided to get a couple of cheap LED controllers and see if I can get them to work. If needed I can easily replace the controller next year without having to touch the rest of the system.

The WLED software package running on an Arduino microcontroller is popular. Hmm, packaged WLED controllers are pretty cheap. For $27 an Aromfentu WLED controller goes in the cart. Since the Aromfentu looks a bit basic, a more programmable controller would be good to experiment with. K-1000C controllers seem to fit that bill, so drop another $37.

Nothing left but lights. The good news is that LED pixel lights are surprisingly affordable. The target is pixel strings, so grab a Rextin WS2811 Pixel String. LED strip lights are widely used, so add a BTF Lighting WS2812B strip. A string of Fairy Lights was kind of cute, so for $10 why not?

These strings were good for basic testing but wouldn’t show any of the patterns that you display on a Mega Tree.

For that testing an 8 pixel by 32 pixel panel made up of WS2812B LEDs is perfect. At $17 it is a no-brainer to add to the testbed.

Add in a few packages of the electrical connectors for the LED strings and I should have all of the pieces I need. Specifically, the pieces needed to learn what pieces I really need.

Watching TV is a bad idea for many reasons. Over the past few years I’ve caught random episodes of various TV shows featuring Christmas decoration and outdoor lighting. The people featured on these shows have gone totally over the top (big surprise). But they’ve introduced new technologies I wasn’t aware of – computer controlled lighting and Mega Trees made with this lighting.

The basic idea is that each individual light is separately controlled – not only on/off, but also brightness and color. The lights can be updated 10-30 times a second. Individual control plus rapid updates means that you can create dynamic effects – even do video on your Christmas lights!

All of this technology finally got me into the Christmas spirit. As a bit of background, I admire The Grinch. The only thing I don’t like about him is how he went soft in the end. Ebenezer Scrooge was also OK, at least until he got ghosted. Christmas decorating is something done under duress.

When I first mentioned making a Mega Tree, She Who Must Be Obeyed asked “who are you and what have you done with RussD?”

Step one was a bunch of research. I discovered that there are three components to a Mega Tree: a light string, a controller, and a power supply. Light strings are (wait for it, wait for it…) strings of lights. LED lights. With a tiny computer built into each LED. These individually addressable LEDs are generally called pixels.

There are many types of light strings: 5V, 12V, and 24V. Three to 300 LEDs per meter. Multiple communications protocols. Strips of lights – basically LEDs attached to a half inch wide strip of tape. String lights, with the LEDs connected by wires. Various degrees of waterproof ranging from none to IP68 water resistance. Individually pixels can be controlled, or groups of three pixels are bundled together. Different communications protocols are used with different lights. The pixels might be three color or four color – three color is RGB (Red, Green, and Blue) and four color is RGBW (Red, Green, Blue, and White). RGBW produces a purer white than the white created by combining RGB.

Depending on your needs, pixel controllers range from under $10 to several hundred dollars. Power supplies range from a USB wall wart to several hundred watts.

Finally, Mega Trees are outdoors. In bad weather. Meaning that all of the electronics need to be designed for outdoor use and water/weather resistant.

All of the research left me educated and confused. Fairly common. OK, except for the educated part…

In theory there is no difference between theory and practice. In practice there is.

With these words of wisdom I began my journey small: rather than starting with a Mega Tree, I would start with a breadboard technology demonstrator to see if I could light up and control a single light string. Based on that experience I could either work up to building a full tree or decide to hide the evidence and move on to the next project.