How to Assemble Very Small LED Lighted Letters With Mini LP WS2812b, Letters 3d Printed With Building Brick Integration, One Word Above Another

This document describes the assembly of illuminated letters with 3D printed parts letters. It shows the integration of the Neopixel mini LP WS2812b soldered with wires in the housing of the letter. The STL files of the letters can be downloaded from Cults3d Cults3d.

The letters are only 6 cm high and stand on an integrated pedestal of 1,5 cm height. The depth is only 2,4 cm. This is one of the slimmest designs that a Neopixel mini LP with WS2812b can fit into.

The space in the case is limited and this document shows how the Neopixel mini LP with WS2812b can still be mounted.

The letters have two options for stand mounting.

The first option uses an opening for building bricks to mount components of the building bricks.

The second option allows the letters to be connected with a letter connector.

The letters are connected to each other via 3-pin plugs and sockets in order to flexibly put together different words.

Letters from 3d printer, download the construction Cults3d Cults3d

Letter connector from 3D printer, download of the construction Cults3d Cults3d

Building bricks for wire routing, they are included in the download of the letters Cults3d

Building bricks, standard bricks and plates

Building bricks, standard bricks and plates

Example: building brick 2x4 studs amazon

Filament ANYCUBIC PLA 1.75mm white amazon

Filament ANYCUBIC PLA 1.75mm black amazon

mini LP WS2812b amazon

Connecting wires between LEDs amazon

Connection cable to the amazon control unit

3-pin crimpable plugs and sockets amazon

Extension Cable 3 Wire 22 AWG , 3x0.3mm² amazon

Solder

Hot glue

WLED controller with 5V output (for testing the soldering)

WLED Software

Tools

3D Printer

Soldering iron for electronic components

Soldering aid cults3d

Side Cutters

Crimping tool amazon

Needle-nose pliers

Hot glue gun with narrow tip

Tweezers, file, cutter knife

Magnifying lamp

Load the STL parts from Cult3d

1. Letter with pedestal
2. Supports for the LEDs
3. Back panel
4. Illuminated cover

Print the STL parts with the 3D printer

These are the parts to print.

1. Letter with pedestal (PLA black, print with supports)
2. Supports for the LEDs (PLA black, without supports)
3. Back panel (PLA black, , without supports)
4. Illuminated cover (PLA white, , without supports)

After printing the parts, you need to remove the supports of the "letter with pedestal".

Remove the supports and check the parts.

Now check whether the parts can be plugged into each other.

Check whether the building brick fits. Work on the pedestal with a file if it doesn't fit in exactly.

Check als the the letter connectors.. All supports must be removed!!

Check that the socket housing for the electrical connection fits into the opening.

Insert the carrier plate for the LEDs into the letter onthe back side.

Insert the back panel into the letter.

Insert the light cover into the letter on the front side.

If everything fits, you can dismount the letter again.

Tin the solder pads of the LED circuit boards. It is best way to tin-plate them in the panel, because you can fix the circuit boards better on the work bench.

Place a LED PCB in the carrier plate of the LEDs and start soldering with the wires for the connector. Measure the length of the wire.

Here is an example of how the wires should be finally

I won't describe the details of crimping here, because there are already information and videos on the Internet. You can take a look at this one, for example.

How To Crimp Your Servo Connectors https://www.youtube.com/watch?v=Ocmi_OCPduc

Download the print files for the soldering aid from cults 3d cults3d and print it with the 3D printer.

Insert the LED PCB into the soldering aid and solder the wire to the pad Vcc on the "Din" side.

Solder the 2 other wires to Din side.

I recommend to test the electrical function of the soldered connection to assure that there is no short circuit or bad solder point. It is easier to find failure now and not to search for failures when all leds have been connected.

To test the LEDs, you need a WLED control unit and a WLED app or WLED server application. There is enough information on the Internet. Therefore, I assume prior knowledge.

You need to make a connection wire from the WLED control unit to the letter.

One end must be connected to an output socket and the other end to the WLED controller.

The output socket is crimped (similar to the connector described above).

Make sure that the sockets in the case are in the correct order and leave the wires long enough.

Now connect the LEDs to a WLED control unit and check that the LEDs light up correctly and that no error has occurred during crimping or soldering.

I am not describing the installation of the WLED software here. There are many tutorials on the net.

Set the WLED to 10 LEDs and the "Solid" effect for the individual test of the letters.

Now solder more LEDs

The output socket is crimped (similar to the connector described above).

Pay attention to the correct order of the sockets in the housing and let the wires protrude from the pedestal for a sufficiently long time. You can see it in the images below. This gives you enough space of movement to plug the jack into the plug.

Now solder the socket to the last LED PCB and insert the LED PCBs with the STL part into the letter. As an aid to holding the lines, you can use a rubber band.

Turn the carrier of the LEDs and check that the LED PCBs are positioned correctly.

Glue the wires with hot glue. The hot glue should not flow too close to the edge, as the back panel must fit down to the bottom of the carrier for the LED PCB. If it still flows too far, carefully remove the hot glue with a cutter knife.

Now slide the back panel into the letter. If the wires don't press against the back panel, you don't have to glue the back panel. Otherwise, glue it in place with hot glue

Insert the white light cover into the letter from the front side.

Test the single letter with the WLED controller by connecting the input . Then plug a 2nd letter into the output socket and test whether the 2nd letter is also controlled.

You can now create a word combination from the letters. I used the following building bricks for this:

Standard

Plate 5 studs x 15 studs (5N x 15 N), height 3.2mm (H3.2). You can also use other plates.

Brick2N x 4N, H9.6

Brick 2N x 4N, H3,2

Bricks from the 3D printer

If you want to have a nice guide of the wires, download this construction and print it on the 3d printer. It is included in the download of the letters Cults3d

The words should be placed on top of each other.

The feed from the WLED controller starts at the last letter of the word combination, this is the letter N.

The word combination is to be mounted on plates of the building brick so that they can stand stably on a surface and do not fall over. I used plates with 5 studs x 15 studs.

You can also use other plate sizes.

First, the word OSTERN is built.

Plug in a 2x4 stud 9.6 mm brick and a 2x4 stud brick 3.2 mm

together. You need 2 of this assembly.

Insert the 2 assemblies into the opening of the letters "S" and "R".

Download the letter connector from Cults3D and print some with the 3D printer. It is included in the download of the letters Cults3d

Connect the plug and the sockets of the letters and push the letter connectors into the letters.

Place the letter combination on the base plates of the building bricks.

Connect the WLED controller's power supply to the last letter of the word combination, this is the letter "N" and check that the letters are lighted up. To do this, change the number of LEDs in the WLED software to 51.

Now the word „FROHE“ will be built.

Assemble 2 pillars each with building bricks, 2x4 studs 9.6 mm and building bricks for the wire routing. You can download the STL file of the building bricks for wire routing at Cults3D. They are included in the download of the letters Cults3d

Download the letter connector from Cults3D and print some with the 3D printer

Connect the plug and the sockets of the letters and push the letter connectors into the letters.

Push the pillars into the opening for the building brick of the letters "R" and "H".

Take the assembly and push it on the building brick plates.

Now you can connect the letter combination to a WLED controller and apply the WLED software. I describe here the settings for the word combination "HAPPY OSTERN"

The word "FROHE". has 23 LEDs, the word "OSTERN" has 28 LEDs, so a total of 51 LEDs.

Set the number of LEDs to 51.

Create 2 segments named "FROHE" and "OSTERN"

Note that WLED controls the first LED in the letter "N" of "OSTERN" and the numbering starts from the end of the word "OSTERN".

The word "OSTERN" has 28 LEDs. Therefore, the "OSTERN" segment has the Start LED 0 and Stop LED 28.

The stop LED (28) is not included in the segment . The counting method starts at 0 (0 to 27) results in the number 28 .

Check the "Reverse Direction" property.

The word "FROHE". has 23 LEDs.

The " FROHE " segment has the Start LED 28 and Stop LED 51.

The stop LED (51) is not included in the segment. The counting method starts at 28 (28 to 50) results in the number 23.

Check the "Reverse Direction" property.

I have set up a test with the effect "Lighthouse" for both segments.

With this setting, I can see that all LEDs and the correct direction are controlled.

You can now make your personal settings in WLED or assemble other words.

Here are some examples for your decoration. You can rebuilt the word combination on other occassions such as a decadal birthday, a jubilee or personal message for others.