Wireless LED Cube Light

This time I’ll show you how I made very cool looking glowing cube from Rubiks Cube and some cheap electronics.

How I did it - you can check by looking DIY video or you can follow up instructions bellow.

For this project you will need:
Materials:

Rubiks Cube (at least 9 by 9 by 9cm)

Ping pong ball

2 pcs 18650 Lithium Ion cells (or other 3.7V lithium battery)

USB power bank case with electronics

5V LED strip

4mm poly-carbonate (Acrylic)

CA glue

Hot glue

Tools:

Drill and bits

Table saw, band saw jig saw or other cutting tool to cut acrylic

Rotary tool

Hot glue gun

Soldering Iron

Sand paper (320 grit)

Utility knife

Step 1: Preparation

I think you really don't need to introduce this iconic game - Rubik's Cube. Today this game will be the main material for my new project. Except I’ll use not this little one, but his bigger brother. Despite his size, this is also a regular 3x3 fully functional Rubik’s cube, but it’s 9 by 9 centimeters in dimensions. What is perfect for my build.
Because I’m planning to put some stuff inside this cube - first, I need to disassemble it. The easiest way to do it - is to twist top part in 45 degrees and then pull out one corner piece. After that rest of all parts will be removed very easily.

Step 2: Cut Out Internal Plastics

As I mentioned, I’m planning to mount some electronics inside this cube, so I need to make more space in it. So I have to cut all his internal plastic parts by leaving about 8 millimeters to the edge. I found that the best tool for this job is a rotary tool.

After all cuts were made - burs was cleaned with utility knife.

Step 3: Acrylic Parts

The main idea is to separate etch cube part by 4mm acrylic inserts.
By using multiply power and hand tools I cut acrylic sheet to needed parts. It was possible to cut parts by using one power tool, or event hand tool, but I used what I got to make this job as fast as possible. All acrylic parts will be cut in 9 millimeters width to save space inside the cube. You see later why this is so important.

There were a few possible ways how to cut and assemble acrylic parts. I choose mine approach, because In the beginning I thought that this way will be the easiest and at the same time will give the best look at finished product.

Step 4: Sanding

When all cutting was done - all surfaces was sanded with 320 grit sandpaper, to get nice matt finish.

Step 5: Glue Up

Time to start assembling and gluing all together.
I assembled and aligned all the parts as they should be, used rubber band to hold them in place and glued the acrylic parts together in one frame by dropping CA glue at etch joint.

Step 6: Assembling Small Cubes

When acrylic frame is done - to glue cube parts is a piece of cake. The centre part will be glue later, when power on/off button will be installed.

I repeated all procedure to reassemble the rest of the cube. What is great when working with CA adhesive - they hardens very fast. And could be set up in seconds by using CA accelerator.

Step 7: Power Button

Time to get back and finish center piece. As I mentioned before - this one segment will be used as power on/off button. Once again - CA glue, acrylic parts and button found its place.

Step 8: LEDs

As a light source for this cube I’ll use 5V LED strips. I have warm and cool temperature, but for this build I’ll use the warm one.
What is great with 5V LED strips - that they could be powered any power bank or smartphone charger. Because all those devices have 5V output voltage.

Step 9: Making a Bulb

To hold LED strips inside the cube my plan is to glue them at ping pong ball. The goal is to form consistent, 360 degrees glowing light. And the ping pong ball is a perfect shape and size to achieve that.
Used some electrical tape to separate etch crossing LED strip from potential shortage. Next - soldered all three strips back to one with few thin silicon wires.

Step 10: Electronics

The bulb is done, now lets move to the power source. First - electronic part. I used regular power bank designed for one 18650 lithium ion cell.
To be more specific - I needed only electronic board to control the power when the battery will be charged and discharged. At the same time this little board will save battery from overcharge and over discharge too. When LEDs on - energy is draining from battery. When power is off - charger kick in and charges battery back. When the battery reaches the lowest voltage value of 3V, protection circuit will disconnect power supply for the LEDs.

Step 11: Working on Electronics

Because I’m tight on space I have to remove battery positive and negative terminals and USB A connector. All wires will be soldered directly to the board.

Step 12: Power Source and Charger

As a power source I used 18650 Panasonic NCR18650PF cells. Etch of them have 2900Ah of capacity.
With hot glue fixes both batteries together and place LED bulb on top.

Next prepared a hole for charging port.

Step 13: Wiring

Soldered positive and negative LEDs wires to the board, where USB A connector was before. In this view most left ping is positive, most right is negative.
I choose negative wire I soldered power button to turn power on and off at LEDs. I used two 18650 cells and connected them in parallel to get total 5800mAh of capacity. Before connecting batteries in parallel be sure that the batteries are at the same or very close voltage. Both batteries terminals was soldered to the power bank board, where positive and negative terminals was before.

Step 14: Testing

A quick check that everything has been done correctly. Great.

Step 15: Mounting All Inside

Used hot glue to fix power bank board that charge port will be accessible. And later on glued 18650 cells with LEDs.

Step 16: The Last Step

Applied CA glue along the perimeter and close the cover.

Step 17: Final Product

With fully charged battery this cube could last up to 12hours. What is more than enough for me.
When I finished this cube, I thought if this cube is portable and wireless, it will be nice to charge it with a wireless charger. Sadly this idea came to me after build was finished, but I left this goal for upcoming LED lamp builds. And for now - I’ll charge this lamp with regular smartphone USB charger.

I hope this video was helpful.