Christmas Led Star

I made a very splendid christmas star that i want to share with you. It is fairly easy to make and it will be a real spectacular eye-catcher on your wall during the advent season.

The star has a cycle of approx 5 minutes of beautifull animations, one moment it has a icy cold heart and burning rays, than it is shining like a diamond or the leds are running with gradually changing colors. Sadly it is almost impossible to make a nice video that shows realistic colors. So the few shots you see here is faintly reflecting the real beauty.

The star is completely controllable via your smartphone, tablet or computer. It has the following features.

• It has 2 scenes of animated lighting
• The brightness can be controlled
• You can use it as a normal lamp with adjustable color.
• There are 4 timers for automated switching
• It can be controlled by home automation (domotica)
• Software can be updated 'over the air' (OTA)

Making the star is fairly easy but you need some soldering and some sawing skills. And a lot of patience as this project may take some time. It will really keep you off the streets in this corona period. But you will be rewarded with a very nice result and you will find that your relatives and friends want you make one for them too.

Tip: You can also use this project to make a straight ledstrip as a partylight or something like that.

The most important and accurate work is to get a star with the leds evenly distributed. The background is completely up to you. It could be a square, a circle or a star. How do we constuct that star? By marking the path of the ledstrips with molds.

CONSIDER

You have to consider that the dimensions and the software are related to the sizes of the ledstrip. Deviations in the distance between the leds will be noticed. So please stick to the measurements in the drawings to get a nice shaped star where the leds are evenly distributed and lined up.

• 3 meters of WS2812B ledstrip
• a 5 volt wallplug powersupply
• a nodemcu or ESP8266-12E
• some wires
• a mdf sheet of 4mm thick and minimal width 530mm

tip: Dismantle an old network cable, you will have lots of wire!

drawing the outline of the ledstrips and the star

The star is basically a ledstrip in the shape of a star, sticked to a background plate. The shape of this plate is completely up tou you. If you want to save you some time, it could be a square. I thought that a star shaped plate would be nicer so that is what i made.

We start with a sheet of mdf 4mm thick that has a width of minimal 526mm. The standard size in the diy shop is 122*620 but when smaller it can be a bit of a puzzle to get the star out of the sheet. Draw a circle of 580mm diameter. Keep this circle 10 mm from the edges of the sheet. Now draw a smaller circle of 540 mm diameter. Don't forget to mark the center.

On the inner circle you mark 5 dots on equal distance. This is an important step so do this as accurate as you can.

If you have a protractor you can do this by drawing lines with an angle of 72 degrees. (360/5). The dots will have a linear distance of 31,74 mm so without protractor you can mark them this way. Draw line from the dots through the center. The 5 dots are the spots of the leds in the points of the star. Check again that they are at equal distance and drill small holes there.

To draw the path of the ledstrips and the outline of the star, you can make 2 molds. This will really help to get a precisely dimensioned star with evenly distributed leds . Screw the molds on the holes in 2 points and turn them such that they meet like in drawing 2. You can fix them with small screws in place and draw lines around them. Repeat this for the other marked leds. Now that you marked the path of the strips, you can draw the outline of the star along the outside of the path. Keep some mm's betweeen the ledstrips and the edge to have more space for the wiring holes.

Carefully saw the star out off the sheet. Saw along the outside of the drawn outline to be sure that the lesatrip path is untouched. Sand the edges and the front is ready. Remember to keep the drawn lines through the heart as you need them for the inner star.

Seen from the back, the star would ideally look like the first picture. This however is hard to make. In reallity the inside would look more like the second picture. You can accomplish this by sawing strips out of the mdf of the desired width and length. I always make them a bit longer so that i can adjust the length to make it all fit.

Take two of the mdf strips and bevel them so that they can form a point. This is easely done with a hobby knive. Mark them number 1 and 2 and mark these numbers on the star front. Repeat this for the next point with number 3 and 4. When done, you take strips 2 and 3 and make them fit together. How do you glue this together? I make pieces of wood that have at least one right angle. I glue these pieces at the edge of the starfront. They can remain there because they are out of sight. Now you can glue the side strips such that you have a a narrow raised edge at the front.

Keep in mind that wiring may lead from a star-point to the center so drill holes when necessary.

When all the sides are fixed, you can sand the edge on the front smooth and fill the gaps. I always make a paste of epoxy and glassbubbles. With this i can make fillets on the inside that wil make the whole construction very strong. After that you could primer the sides but wait with the front, this needs special treatment.

The star will be hung-up like the first picture.

THE OUTER STAR

We have the ledstrips cut in 5 pieces of 11 leds and 5 pieces of 10 leds. The strips are self adhesive but would probably not attach very well to the mdf. So it can be handy to apply some thin paint or varnish on the spots where the strip should come. Sand after drying to make a well-adhering substrate. Don't paint or sand away your markings and helplines!

It may be helpful to tin the soldering pads first, this makes soldering easier. Where needed you can cut off a small corner at the ends of the strip.

First verify that all will nicely fit. Mark the places where you want to have holes for the wires. Keep these holes as far from the strip as you can because it can be difficult to bent a wire right at the end of the strip. I soldered the wires first, one datawire at the ends in the corners and 3 at the other ands. Now you can put strip 1 in place. This can be a strip with 11 leds. Note the direction of the data line! This is counterclockwise. The last (11th) led covers exactly the hole that you drilled in the point to screw the mold. Repeat this with strip 3, 5, 7 and 9 at the next points. Now place the 10 leds strips, starting with strip 2. Again, note the direction of the data line!

When all the strips are in place, you have the wires stabbed through the holes, underneath the front. there you can solder the connections and fix them with hotglue on the mdf.

The wires can be masked with acrylic paint afterwards so dont worry too much about them. When the star is working, you won't see any wires.

THE INNER STAR (SNOWFLAKE)

For the snowflake you need 1 piece of 5 leds, 4 pieces of 4 leds and 5 pieces of 2 leds. There are 5 parallel connected circuits, each consisting of one piece of 2- and one piece of 4 leds. Because you can't parallel more than 3 strips, there are 2 dummy leds needed. The schematic shows how it is connected. While there is not much space in the center, most of the connections are soldered at the outside.

The best way to line the leds up is to draw circles at leddistance. This helps to get all the leds at even distance from the center.

We need a microcomputer to control the ledstrip, in this case a nodemcu. This has to be programmed. We do this by uploading a softwarepackage.

Update feb. 8 2021:

The software now has several improvements. A.o. a faster webserver, nicer webinterface, a few cosmetic improvements, a log of events and the possibility to set a unicolor via an API. You can setup your own color presets in domoticz. Symply by sending ip_of_star/STARCOLOR=;r;g;b;.

Update feb. 8 2021:

Optimized webpages for smartphone, mqtt functionallity, improved wifi config portal.

DOWNLOAD ESP8266-WS2812B-STAR-V5_7 from onedrive

I made it extremely simple to install the software on your ESP device. Please follow these steps: Download and unzip the file in a folder on your computer. Enter this folder and click on Serial_Communicator.exe, the program will start. Connect the ESP via the usb cable to your computer. You can test now on which com port the ESP is connected. Read the help text to proceed. When the software is installed, the blue onboard led wil light up. Now you can proceed to the chapter "how does it work".

There is a new softwareversion available with a very fast asynchrone webserver, and some other features.

WEB INTERFACE

The star has an extensive userinterface. On the main page you can switch the various scenes on and off. You can set 4 timers for the automatic switching. There is a log that shows you what happened. Furthermore there is a page with information on the settings, switching scenario's, file system, etc.

CONNECT TO WIFI

Once the software is uploaded, the nodemcu boots and the blue onboard LED and some leds in the snowflake are lighted up continuously. This means that an accesspoint (AP) has been opened. .

Now open the wifi settings on your laptop, phone or tablet. You'l see a netwerk called ESP-123456 or similar. Connect to this network with password 123456789 and browse to 192.168.4.1.

Enter your credentials and follow the further instructions. Don't forget to set the administrator's password. Default this is 0000.

When successfully connected, the ESP will show you its ip-address (make a note of this), than reboots. When the led flashes 3 times during reboot, it is connected to your network.

Now you can browse to the provided ip-address and you will enter the homepage of the star. Login with "admin" and the administrator's password. Now you should go to "settings/timeconfig" and provide the data for the timekeeping. When this is done, you can setup timers for the automated switching. For the rest the settings are self-explanatory but there are help buttons.

CONTROL WITH API

The star listens to direct commands like "ip-of-star/STAR=ON1", "ip-of-star/STAR=ON2", "ip-of-star/STAR=ON3"or "ip-of-star/STAR=OFF". Also it can be switched with mosquitto messages. These can be used by your domotica apps.