LED CUBE - CUBE LED - 8x8 - 3D

The original idea https://www.printables.com/model/337027-cubled-led-cube-8x8-matrix-384-leds was a perfect starting point. Thanks to @Whity for his incredible work and really helpful manual for the basics and electronics requirements. I will not repeat the main build here, because it is similar, only with some different designed cube parts and a bit more to solder.

Electronics

Additional parts required for the electronics in comparison to the original:

• 3.3V Relay
• USB-C port inlet
• Mini switch
• DHT11 or 22 temperature sensor
• Experimentation breadboard/plate for the electronics assembly as well as a socket for the WEMOS if it has to be replaced in any case.

I added also a level shifter, because normally the LEDs should be driven based on a 5V output. It is placed under the WEMOS socket, but it will run also without. I used a lot of LEDs of the same type in other projects and all were running perfectly with the 3.3V WEMOS output directly wired without any issues. I assume longer cables could make problems with a 3.3V based controller, but here it should work.

The 3.3V relay is powered directly by the 3.3V outlet of the WEMOS D1 Mini when the 5V mini switch placed in the outer hull is set to -on-. The relay then powers a second 5V circuit with a current up to 7A only for the LEDs. To be able to shutdown the cube completely, a second switch similar to the original powers off the UBEC. Because when powering the UBEC all the time, the battery will be empty within few days. 

I use a 4A LiPo loading module wired directly to the USB-C inlet and of course a cell balancer board. The parts are placed under an additional separator.

Remark: It gets really warm inside during loading (around 60 degrees). After some days of running and charging the cube, I would recommend not to exceed 2A loading current. The 4A loader was a bit too optimistic I think.

The two blue sockets which are currently bridged are for connecting switches like shown in the next pic.

Printing

All internal parts holding the electronics are printed using PETG V0 certified prusament. As @Whity already mentioned in his description, the cube gets warm inside, especially when high brightness values are set or during loading. I don't know if it makes the thing much safer, but it gives a good feeling.

For the outer surfaces I used transparent PVB. It was a little bit tricky to switch to PETG again after the third layer. It needed some redesign to get the adhesion between the layers right. 
I added a print pause for changing the filament and setting the temperature to 260 deg for the first two layers after the filament switch. Then for the rest, I used recommended 240 deg again. The overtemperature for a short time should add some heat to glue the PVB and PETG together I thought. At least it worked at the end...

Build

As said in the original…. some patience is needed. I added some features to the structure for a good “fitting”. I needed no sanding at all and the cube is a perfect cube with very good tolerances using only some tape fixation during gluing the parts together.

The two violet stripes were enough for folding the parts together after applying the glue. I did not use 2K, but UHU Hart. It did the job so far.

The lid is also fixed by some magnets… currently there are 4 6x2mm round magnets in a vertical orientation. Eventually it makes sense to add 4 more, but it holds good enough also if the cube is carried upside down.

A complete rebuild of the incredible LED Cube https://www.printables.com/model/337027-cubled-led-cube-8x8-matrix-384-leds from scratch. Why?

I wanted a bigger size of the cube and decided to design it 110x110x110mm. I added a external USB-C port for loading the LiPo without having to open the cube and also a switch accessible from outside to power the WEMOS off/on.

Pimped the electronics a little bit, added a seperate 5V power circuit for the LEDs toggled by a relay. This enables the accessible power switch for the controller.

Added a temperature sensor and sensing of battery voltage using WLED usermods.

The mechanical parts were slighlty redesigned for a good fit and the wanted size.