(upbeat synth music)
- We've reached the end of our journey.
By now, you should have some boards from OSH Park,
and some electrical components from DigiKey.
We get to solder everything up and see if our badge works.
The first thing I like to do is print out
my bill of materials so I can use it as a reference
while soldering.
Notice that I printed mine without links
to the product pages.
We won't need them.
Grab one of your bag of parts from DigiKey,
and take a look at what's in it.
Here, I have my ten microfarad capacitors.
Make sure that the manufacturer's part number
matches up on the BOM: ECA1HM100.
Take a look at the ref des on the BOM.
The ten microfarad capacitor is to be used for C1.
Write C1 somewhere on the bag's label so you know
where the part is supposed to go on the board.
Do this for all your parts and double check
that you have everything according to the BOM.
If your board was cut out of a panel,
you might have tabs along the sides.
I recommend using some good cutters
to get rid of these and then sanding down the edges.
Because the dust for most PCBs can be harmful,
it's recommended that you sand
in a well-ventilated area while wearing
some kind of respiratory protection.
One of these cheap masks with at least an N95 filter
should be sufficient.
At least according to the MSDS data sheet for FR4 material.
If you're curious, I'm working with a soldering station
and I set my temperature to 700 degrees Fahrenheit.
I'm using Sparkfun's lead free solder,
with water-soluble flux core.
For any rework that I might have to do,
I keep my water-soluble flux pen near by.
Normally when I solder,
I like to start with components in the middle of the board
and work my way out.
This allows you to get your iron in hard to reach places.
However, for this board, we'll start
with the shorter components and work our way
to the taller components.
To start, find R1 and R3 which should be
your 22k Ohm resistors.
Bend the leads so that they can be inserted
into the resistor foot prints,
and place them into their respective spots.
On the back side, bend the leads out
so that the resistors stay in place.
Repeat this process for the rest of the resistors,
making sure that you put the correct resistor
in the right spot.
Pay attention to the refdes markings on the board.
With all the resistors in place,
tun the board over and solder all the leads.
Remember to hold the soldering iron
so that the tip is touching both the component lead
and annular ring.
Wait a moment and then feed solder
into that three way junction.
When you get a nice little mountain shape,
remove the solder first and then remove the soldering iron.
Use a set of clippers to cut the excess leads.
Make sure you don't cut into the solder joint.
I like to do these 7555 chip next.
You might have to bend the leads to get it to fit.
My trick for this, is to rest the chip on it's side
on a hard surface and then slowly rotate it
to bend all the leads at once.
Repeat for the other side.
Place the 7555 on the board.
Note that the notch should be pointing
to our pin 1 marker on silk screen.
Caefully flip the board over.
Because the 7555 is taller than the resistors,
we can rest the board on the chip
so that we can solder all the leads.
Place the transistor next.
There's no clear indication as to
which was the transistor should go.
However, if you look closely,
you should see that there is more space
between the silk screen corners
and plated through holes on one side.
The transistor's round edge should be placed
facing the direction with more space.
Flip the board over, bend the leads out
to have the transistor stay in place,
solder the joint, and then clip off the excess.
Place the switch next.
The orientation does not matter.
Once again, you can rest the board on the switch
to get at the leads.
If necessary, you can also put
a pen, pencil, screwdriver or other object
under the opposite side of the board
to keep the board parallel to your work surface.
Solder the leads and clip off the excess.
Place the battery holder and note
that it should line up with the outline drawn in silk.
This will ensure that the polarity is correct.
Flip the board over and balance it on another object.
Solder the battery holder leads.
They're short enough that you don't have
to worry about clipping them.
Take a look at the foot prints for the two capacitors.
C1 and C2.
You should see a little plus symbol
in silk screen showing the positive terminal.
The filled in semi-circle is the negative terminal.
Take C1 and look for the minus sign markings down one side.
This is the negative terminal and it should be placed
in the through hole with the filled in semi circle.
Bend the leads to hold it in place.
Do the same for C2.
Solder all four connections and then clip the leads.
There are no clear polarity markings on the LEDs
as we covered them with our silk screen canvas.
If you look at the layout for D1 and D2,
you can see that the front fabrication layer
shows the flat edge of the LEDs pointing down.
That means the top pin, the one closest
to the notch cut out, is the positive pin.
If you look closely, most LEDs will have a flat edge
on the ring around the bottom of the component body.
This flat edge denotes the cathode,
or negative pin of the LED.
If the LED does not have this flat edge,
then the longer pin will almost always
be the positive pin or anode.
Place the LEDs with the positive pins
going closer to the top of the board.
Bend the leads, solder them and cut off the excess.
I always like to clean my board
using a stiff bristle brush and some rubbing alcohol.
water-soluble flux can be slightly conductive
and mess up some of your electrical signals,
so cleaning it off is a good idea.
Once you've scrubbed the joints,
dry them off using a napkin or compressed air.
I like to use kimwipes, as they don't leave lint
behind on your board.
And now, the moment of truth.
Place your battery into the battery holder
with the positive side facing up.
Flip the switch and hope that nothing explodes.
With some luck, you should see the LEDs
slowly start to fade.
Take a moment to enjoy the fruits of your labor.
We've come a long way considering
we designed this board from scratch.
Feel free to get creative and draw
something fun on your badge.
Now, wear your badge to your next event
or out just for fun.
If you need additional resources,
DigiKey's site can help you out.
Head to digikey.com.
Under resources, click EDA and design tools.
Here, you can get more information
about electronic design automation tools including KiCad.
If you're thinking about moving to production
for your device, head to the maker.io page on DigiKey.
This will give you some good materials and suggestions
for taking the next steps to sell your product.
That concludes our introduction to KiCad series.
I hope you had fun along the way and you feel ready
to make something of your own design.
When you make your badge or other project with KiCad,
let us know by sharing photos of it
on Instagram or Twitter with the hashtag #MakeWithDigiKey.
If you wanna see more videos like this,
please click subscribe and I hope to see you
at the next event rocking your sweet custom badge.
(funky music)