Hobby Components V2 4x4x4 LED Cube Kit User manual

Hobby Components
V2 4x4x4 LED Cube Kit
Build Guide
Document version 1.0

PLEASE NOTE
This build guide is for version 2 cube kits only. If you have an older version kit (V1 or V1.1)
you can find the correct build guide on our blog site here:
https://blog.hobbycomponents.com/?p=412
To make this kit as easy to build as possible we have designed it to only use through-hole
components. However, some familiarity with soldering is required to construct this kit .
DISCLAIMER
This document is provided "as is". Hobby Components Ltd makes no warranties, whether
express, implied or statutory, including, but not limited to, implied warranties of
merchantability and fitness for a particular purpose, accuracy or lack of negligence. Hobby
Components Ltd shall not, in any circumstances, be liable for any damages, including, but
not limited to, special, incidental or consequential damages for any reason whatsoever.
COPYRIGHT NOTICE
This document, including content and artwork is copyright of Hobby Components Ltd and
may not be reproduced without written permission. If you paid for or received a copy of this
manual from a source other than Hobby Components Ltd, please contact us at
[email protected]

Before You Start
Kit contents
The first thing you need to do is check that all the components are enclosed in your kit. Here is a
check list of all the components included in the kit:
QTY
Description
1
Version 2 4x4x4 Cube Kit PCB
16
180 Ohm resistors (BRN, GRY, BLK, BLK, BRN)
2
220 Ohm resistors (RED, RED, BLK, BLK, BRN)
1
10K Ohm resistor (BRN, BLK, BLK, RED, BRN)
3
100nF ceramic capacitor (marked 104)
1
470nF ceramic capacitor (marked 474)
1
SR1100 Diode
1
28 pin IC socket
1
18 pin IC socket
1
ULN2003 18 pin IC
1
ATMega328 28 pin IC
1
Push button
1
2.1mm DC socket
1
5 Pin right-angled header (may be supplied as a 40 pin breakable strip)
20 + spares
Male to female sockets (supplied as a 40 pin breakable strip)
4
5mm white LEDs
64 + spares
3mm LEDs
25cm
Solid core wire
1
USB to 2.1mm DC cable

Required tools
In order to build the cube, you will need the following tools:
1. Soldering Iron (Ideally with a fine tip)
2. Solder
3. A small pair of snips or side cutters
4. A pair of small, long nose pliers
Recommended
4x4x4 V2 Cube kit LED template (SKU: HCPROT0101)
OR:
A piece of perspex / plywood which will be used as a jig for soldering the LEDs that
make up the cube
3mm drill bit and drill

Part 1: Building the PCB
Soldering notes
Take the PCB out of your kit and you’ll notice that one side of the PCB has white silkscreen
printed on it with the other side being completely blank. All components, apart from the male
to female sockets, will be soldered to the silkscreen side of the PCB.
Soldering tips:
When soldering components to a circuit board it is always best to start with the smallest
components first. This helps keep the board flat and stops access to pads from being
restricted by larger components. We have deliberately ordered the steps within the guide so
that components are soldered in order of height.
The first step is to start by soldering the resistors. In your kit these will be marked
appropriately. The orientation of most of the components doesn’t matter but we will point out
any components where the orientation does matter. In these cases it is important to make
sure you have them inserted correctly.
Unless otherwise stated, solder components to the PCB by inserting their legs through the
appropriate pad holes on the silkscreen side of the PCB, then flip the PCB and solder the
component legs to the PCB pads on the opposite side (non-silkscreen side).
For components with flexible legs like resistors and capacitors you can keep them held in
place by splaying the legs outwards slightly. Once soldered any excess leg can be trimmed
using a pair of snips or side cutters.

When soldering components with multiple pins it is recommended to solder one pin first,
then check that the component is still sitting flat to the PCB, then solder the rest of the pins.
In the case of IC sockets, solder pins in opposite corners of the socket first. That way if the
socket isn’t sitting flat it is then easy to reheat the soldered pads to flatten the socket before
soldering the rest of the pins.
With these tips in mind we can now start soldering the components to the PCB. Solder each
type of component in the following sequence…
Step 1: Resistors
16x 180 Ohm resistors R2 to R17
(marked BROWN , GREY , BLACK,
BLACK, BROWN )
The orientation of the components doesn’t
matter.

4x 220 Ohm resistors R19 to R21
(marked RED , RED , BLACK, BLACK,
BROWN )
The orientation of the components doesn’t
matter.
1x 10K Ohm resistor R1 (marked
BROWN , BLACK , BLACK, RED ,
BROWN )
The orientation of this component doesn’t
matter.

Step 2: Diode
1x SR1100 Diode D5
Note that the orientation of the diode is
important - solder it to the PCB with the
silver band pointing to the edge of the PCB.
Step 3: IC sockets
1x 18 pin & 1x 28 pin IC socket
In both cases solder the sockets with the
notch end of the socket pointing into the
PCB. Be careful when inserting the sockets
that none of the pins bend under the socket
instead of going through its pad hole - they
should drop into holes without any
resistance.

Step 3: Serial port
1x 5 pin right-angled header
This may be supplied as a 40 way strip
which can be broken into a 5 pin section.
Solder this header with the pins pointing to
the outside of the PCB.
Step 4: Capacitors
3x 100nF ceramic capacitors C1, C2, &
C3 (marked 104)
1x 470nF ceramic capacitor C4
(marked 474)
The orientation of the components doesn’t
matter.

Step 5: Switch
1x Push button switch
Note that the orientation of the switch is
important - referencing the image, insert
the switch into the PCB so that the pins are
on the top and bottom sides of the switch.
Step 6: 5V Power socket
1x DC Socket

Step 7: Cube sockets
20x Male to female sockets P1 to P20
The male to female header pins will be
supplied as a 40 pin strip. Using a pair of
pliers or snips they can be broken into
individual pins. The outer plastic casing can
either be left on the pin or removed
depending on your preference.
These pins are the only component that is
soldered to the non-silkscreen (top) side of
the PCB.
Step 8: Base LEDs
4x 5mm LEDs D1 to D4
The orientation for the LEDs is important –
the short leg of the LED (called the
cathode) should be oriented to the outside
of the PCB. You can also identify the
cathode side of the LED as it has a flat
edge at its base.

Step 9: ICs
1x 28 Pin ATMega328
1x 18 pin ULN2803
Insert the ICs into their sockets. Note that
the orientation of the IC’s is important –
at one end of each IC you will notice a
semi circle cut into the case. When the
IC’s are inserted into the board these
should point to the inside of the PCB.

Part 2: Building the LED cube
To build your LED cube you will need to solder the 64 3mm LEDs supplied in your kit into four
sets of 4 x 4 grids. This will take a little time and so it is important that you understand how to
construct these grids before starting.
Template
If you purchased the optional template PCB then you will be able to use it to accurately construct
each of the four 4x4 grids.
If you don’t have the optional template then it is recommended that you first construct yourself a
jig/template as this will allow you to construct the grids quicker and with more accuracy. To do
this you will need a piece of perspex, plywood, or any stiff material you can drill holes into,
measuring at least 8cm x 8cm.
Using a drill with a 3mm bit, drill 16 holes arranged in a 4x4 grid with their centres spaced 0.9”
apart…
.
Note that the above diagram is available as a separate PDF file and can be downloaded from our
forum ( https://forum.hobbycomponents.com/viewtopic.php?f=133&t=3009 )

Before you start building here’s a few tips:
Tip 1 : Before you start soldering your LEDs together we strongly recommend testing each LED
first. You can do this by using your newly built PCB as an LED tester! Simply power the PCB up
by connecting the supplied USB cable, then check each LED by inserting it into the two sockets
shown in the image below.
Make sure to connect the LED to the two sockets shown in the image and with the shorter leg of
the LED inserted into the outer socket. With the PCB powered the LED should randomly turn on
and off as the cube runs through its demo.
Tip 2: When bending the legs of the LEDs use a pair of long nose pliers. This will help to avoid
applying mechanical stress to the base of the LEDs as you bend the legs.
IMPORTANT: Avoid applying mechanical stress at the base of the LED. Twisting or
bending the legs directly at the LED base may cause damage to the LED causing it to
work intermittently or even fail completely. Use pliers as shown.

Step 1: Bending the LED legs
The first step of constructing the cube is to bend the LED legs. The LEDs for columns 1 to 3 will
require both legs on each LED bending and LEDs for column 4 will only require one leg bending.
Start by taking 48 of the 3mm LEDs out of your kit bag. Note that the LEDs have a short leg and
a long leg. The short leg is the LED negative (cathode) side and the long leg is the LED positive
(anode) side so it is very important to make sure you are bending the correct leg.
Using a pair of pliers, bend all 48 LEDs as shown in the image below.
Note that the short leg is bent slightly higher from the base of the LED than the long leg. This is
because when the LEDs are soldered together into a grid the short leg of each LED will have to
cross over the long leg of the LED to its left without touching it.
Don’t worry if you make a mistake – we provide extra LEDs in the kit to help cover for any
problems.

Once you have 48 LEDs bent you can then bend the LED legs for column 4. Take 16 more 3mm
LEDs out of your kit bag and bend each LEDs long leg in the same way as you did for the
previous LEDs; however this time DO NOT BEND the short leg...
You should now have a total of 64 LEDs, 48 with both legs bent, and 16 with just the long leg
bent.
Step 2: Making the first row
The next step is to take some of the LEDs you have just bent and solder them together to
make the first row of 4 LEDs. If you purchased the optional template PCB you will now need
this to construct the grids. Otherwise please see the section of this document titled
‘Template’ for instructions on how to make your own.

Take 3 LEDs that have both legs bent, and one LED that has just one leg bent. Solder them
together to make the first row with the LED that has the single leg bent on the far left hand
side. Make sure that none of the short legs are touching the long legs where they pass over
them.
Step 3: Making the first 4x4 grid
Repeat step 2 three more times until you have 4 rows of LEDs with their short legs soldered
together…

Next, solder the long legs together…
Step 4: Making 3 more 4x4 grids
Once step 3 has been completed with all 4 row and 4 column legs soldered together, the
entire 4x4 grid can now be carefully removed from your jig and set aside.
The next step is to repeat steps 2 & 3 to make 3 more identical grids until you have a total of
four 4x4 grids…

Step 5: Insert the girds into your PCB
Now that you have the 4 grids constructed they can be inserted into the LED sockets on your
PCB.
Orient your built-up PCB so that the silkscreen (component) side is facing down and the DC
power socket is to the rear of the PCB.
Next, take one of the 4x4 grids and using a pair of long nosed pliers carefully insert the
column legs (long legs) of the grid into the first row of LED sockets (P1, P5, P9, & P13) so
that the LEDs are pointing towards you...

Now repeat the last step with the remaining 3 grids, inserting them into each following row of
LED sockets. Note the last row of sockets (P17 to P20) at the rear edge of the PCB should
be left unconnected...