Project Steps

Joey Hudy #2

A bit of information about LED’s

All LEDs have a positive (+) and a negative (-) lead. As you can see in the picture, the positive (+) lead is longer than the negative (-) lead. You will always be bending the negative (-) lead. The official term for the negative lead is “cathode” and for the positive lead it is “anode.” For these directions we will use “short” and “long.”

Guide Sheet

I used this as my template. If you ever get confused (easy to do) refer back to the guide sheet. This will tell you the placement and orientation of the LEDs and how to bend their leads.

Each circle has 2 dots. The one with the arrow is the negative (-) lead and the one standing alone is the positive (+). This diagram shows you which way to bend your negative (-) leads.

Connecting your LED’s

This is an enlarged picture to show the use of the Helping Hands to hold your work.


1) Start with the center hole. Fold down the negative (-) lead on the right side. 2) Place the second LED in as shown. Solder them together. Don’t worry about the end of the LED being too long. We will be trimming them. 3) Place the third LED in as shown. Solder them together. Continue on until all 9 LEDs are soldered together.

Before cutting the extra wire, take another look to make sure all your LEDs are going the correct way and you folded down the negative (-) lead in each case. This is the time to catch a mistake; you can always unsolder and fix it. Using your wire cutters, cut off the extra wire. Mostly these should be on the 4 corners.

Do the same 2 more times.

You should have three 9-pin LED squares

Solder all 3 levels together

Now the tricky part starts: stacking them together.

Put one LED piece back into the foam. You can find something to slide in between levels as shown.

Put your 2nd layer on. You will be soldering the positive (+) lead to the corresponding positive (+) lead on the next layer as shown. You may need to bend the wires so they meet.

Please note that the picture above is showing how to stack the layers. They have not been soldered together. If you connect one positive (+) to a negative (-) your LED will not light up in the end.

Do the same with the 3rd layer

This is what you should have in the end. As long as all the soldering is good the LEDs will still shine. Set your LED “cube” off to the side. Let’s work on the PCB.

Set this aside while we work on other parts. We will put this onto the pcb later

Lets start with the Resistors

The Resistors come with their leads straight. You need to bend them as shown. There is no polarity (+ or -) to these, so you don’t have to bend a particular wire. Just bend either one down.

Place each resistor into the board. Solder each in on the back of the PCB. There is no right or wrong way for these. I prefer to have mine going in the same direction.

Black Wires

You will need to take your wire strippers and strip off a bit of insulation at each end. You will be soldering the top and the bottom, so strip off enough to do so. You may also choose to strip off all the black insulation. Either way is fine.

You will need to cute each wire to fit. One goes on each level of the LEDs. So you will have a long, medium and a short one.

Attaching the 3 black wires.

Look at your black wires. You need to solder each of them to the correct level. First look for the very first LED you put into the foam. This is the wire you will solder to the negative (-) leads. Solder your short black wire to the negative (-) lead of the LEDs on the bottom level.

Solder your medium black wire to the negative (-) lead of the LEDs on the second level. Solder your long black wire to the negative (-) lead of the LEDs on the top level.

Insert the tower into the PCB

Take your time and get each wire into the correct hole. It’s kinda like a puzzle. Once you’ve succeeded in doing that, solder the wires in place on the back side. Then give yourself a pat on the back!

Next the IC’s

The first piece that goes in – goes in a curtain direction.

You will see on the PCB a little 1/2 circle. You will also see a notch on the piece. Line up the 1/2 circle with the notch. picture 2

Solder. Do on both pieces.

Next gently place in the IC’s. You will need to be careful and take your time.

Arduino Pins

You have 1 long piece of pins.

You need to break them apart to the correct length to fit into the arduino.

Place each piece into your Arduino. This will make the fit better.

Place your shield on top of the pins.

Solder the pins onto the shield. Doing this on the top of the shield.

Connect your Arduino to your computer. Install the test code, found here. You should see all the LEDs go on. I usually take mine into the bathroom – nice and dark!