2. LEDs & Soldering 💡

This step is by far the most time consuming and difficult step. Don’t Worry! Take it slow, if something doesn’t work it’s better to move away and come back to it later rather than risking blowing up s

For this part of the build I recommend creating a cardboard mock up which you can draw on to help understand the wiring and snaking of the data line. It can be quite confusing so referring to a mockup can be very useful.

Explaining The Wiring Diagram

One of the most difficult parts it understanding the wiring. We have 3 total data loops back on ourselves with a dodecahedron. These are:

2->3

4->5

6->7

These are where you will want to have your data cables in the frame channel.

The direction of data on the LED strip is shown by the arrow -> in the wiring diagram above.

Starting at Vertex A (where the exit hole is). You'll come across. The best way to visualise this wiring is with a cardboard mock up.

Connections:

• Every Negative terminal is connected to every negative terminal at that vertex

• Every positive terminal is connected to the other two positive terminals at that vertex

• The data line is one single snake that runs in a specific pattern around the whole cube, and you have to follow the data direction of the LEDs (Most LED strips have arrows to show data direction).

I would recommend hot gluing the data wire before adding the LED trip. Then using hot glue to assist with sticking down the LED strip over the top.

Starting the wiring

I recommend starting at the wire input hole. This is where our cables will exit the cube model to our controller. You can trim off the first LED and wire your own. This also assists with adding the connections at every vertex.

You may want to extend the wire off the LED, I used 1M additional wire to make it more portable and easy to place in different areas. Close to an outlet.

The cube consists of 12 strips of LEDs. To cut your strips, use a sharp Stanley knife or some flush cutters. The solder pads can sometimes be very small depending on the manufacturer so I would recommend cutting after the last LED, right up against the next. Then trimming off the following LED before cutting another strip. This does waste one LED every length, but it allows you to solder on the full solder pad at each end rather than a half a pad and makes soldering much easier.

To prepare the strips it’s better to pre-solder them before installation. To do this, tape them to your desk or a piece of scrap wood, heat up the solder pad on the strip with the tip of your soldering iron, and push a small bead of solder onto the strip until you have a small mound of solder on the pad. Do this for all 6 pads per strip (3 on each end).

To begin with, glue down the first 3 strips, starting from the input, being mindful of the direction of the data flow. I recommend adding 3 dabs of super glue under each strip as the backing tape tends to peel up after a while.

At each connection, I would recommend having all strips glued in, even if they are not being used in the loop yet. Connecting all 3 power terminals together will ensure the voltage is evenly distributed across all the LEDs in the project.

BEFORE gluing any strips that have a data jump (see schematic), you need to first solder a long strip of wire from the end of the data line, and fold it back to the other side of the strip. When gluing to the frame, this wire is pushed through the small tunnel in the 3D print so that it comes out on the data input side, to go to the next strip.

This process repeats all the way around the shape, at the end of the data loop only connect the power terminals, the data terminal doesn’t need a connection.

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NOTES

This took a reeeeally long time, so be patient and take it slow. Here are some more tips for this step.

• Do not hold the soldering iron too close to the LEDs as this can damage them.

• Try not to over heat your solders, you could again damage the strip or melt the 3D printed frame underneath.

• If your solder doesn’t seem to stick, try scratching the surface of the copper with a knife

• Don’t do too much at once, you may loose track of the layout and solder something incorrectly

• Double and triple check your connections!! If you solder a positive to negative, or the data line to the wrong terminal you can destroy some LEDs or even full strips

• Don’t leave conductive wires near the frame, I did this and one fell onto the connection when it was turned on… I blew up 4 strips… not a fun experience.