How to Assemble an Arduino Shield

By John Nussey

If you plan to have any fun with your Arduino, you’ll need to do some soldering. Soldering requires learning a great amount of technique, and you develop good technique with practice. In this example, you find out how to assemble an Arduino shield. A shield is a specific printed circuit board (PCB) that sits on top of the Arduino to give it a function.

There are different Arduino shields for different functions. The one used in the example is the proto shield kit, which is essentially a blank canvas to solder your project onto, after prototyping it on a breadboard. In this example, you see how to assemble the bare minimum of the kit to attach it to your Arduino and then how to build a simple circuit on it.

Arduino proto shield
A complete Arduino proto shield.

As with many Arduino kits, you need to assemble this shield yourself. The basic principles of soldering remain the same but may vary in difficulty as you encounter smaller or more sensitive components.

Using stripboard instead of a PCB for Arduino shields

Specially designed shields are made to fit your Arduino perfectly but can often be relatively expensive. Stripboard, or perfboard as it’s sometimes known, provides a cheap and highly versatile alternative. Stripboard is a circuit board with strips of copper and a grid of perforated holes that you can use to lay out your circuit in a similar way as on a breadboard.

The pitch of the holes and the layout of the copper strips can vary. The most useful pitch for Arduino-related applications is the same as the pitch on the Arduino pins, 0.1 inches (2.54mm), because that pitch allows you to build on the layout of your Arduino to make your own custom shields. You can buy stripboard in various arrangements of copper strip as well, commonly either long copper columns that run the length of the board or sets of columns three rows deep (usually called tri-board).

Check out these 10 places to find Arduino parts and components.

Arduino shields: Laying out all the pieces of the circuit

When assembling a circuit, your first step should always be to lay out all the pieces to check that you have everything you need. Your work surface should be clear and have a solid-colored cover to make things easy to find.

This image shows the Arduino proto kit laid out in an orderly fashion. It contains the following:

Arduino shield componnts
All the parts of the shield laid out.
  • Header pins (40×1)
  • Header sockets (3×2)
  • Pushbuttons
  • LEDs (various)
  • Resistors (various)

Some kits may ship the PCB only and leave you to choose the headers that are connected. Remember that there is no right or wrong way as long as the assembly suits your purpose.

To assemble this shield, you can work from a picture to see the layout of the components, but for more difficult ones, you usually have instructions. In this example, you walk through the construction of this shield step by step and point out various techniques for soldering along the way

Assembly of an Arduino shield

To assemble this kit, you need to solder the header pins and the pushbutton. Soldering these pieces allows the shield to sit in the header sockets on your Arduino, extending all the pin connections to the proto shield. Note that some versions of the proto board have header sockets (or stackable headers) rather than header pins.

Header sockets have long legs so that they can sit on top of an Arduino in the same way as header pins but also allow sockets for another shield to be placed on top. The benefit of header pins is that your shield is shorter and needs less space for any enclosure. Header sockets are used in the assembled Arduino shield. They are the black sockets that run down either side on the top of the board, with pins extending underneath.

In this example, you use header pins and do not connect the ICSP (in-circuit serial programming) connector, which is the 3×2 connector in the center right of the Arduino Uno. The ICSP is used as an alternative for uploading sketches with an external programmer as opposed to the Arduino and is for advanced users.

Header pins in an Arduino shield

First you will need to cut the header pins to length. This kit uses a length of 1 x 40, which is 1 row of 40 pins. The plastic strip has a notch between each pair of pins that you can cut to divide the pins neatly. To secure the shield, you need lengths of 6 pins (for the analog-in pins), 8 pins (for the power pins), 8 pins (for the shorter row of digital pins), and 10 pins (for the longer row of digital pins).

Use your clippers to cut the header pins to the correct length; you should have 8 pins remaining. (Put these in a box for future use!) The pins should fit exactly because there is a 2.54mm (0.1 inch) pitch between them, which matches the board. You need to look for this same pitch if you’re buying header pins of any other connectors separately.

Arduino header pins
Close up of the header pins.

Now that you know where the header pins go, you can solder them in place.