Touch Board Pro Kit

Build more functionality into your Touch Board project with this flexible shield

We developed the Touch Board Proto Shield to provide an easy and robust way to add functions to your Touch Board. The Touch Board Proto Shield makes it easy to connect to your Electric Paint sensors, no matter what your project format.

The Touch Board Proto Shield features screw terminals for wired connections, a convenient ground plane for using shielded cable, a prototyping area, and all pins brought up to the shield for your project. These features are all explained in further detail below.

If you’ve never soldered headers on before don’t worry. Just follow our step-by-step tutorial below to attach the sockets and headers, and start your next project!

We love it when you share your projects! Post your project on Instagram, YouTube, or Twitter, and make sure to tag @bareconductive or use #bareconductive. You can also send your videos and photos to info@bareconductive.com so we can post them on our site for the world to see.

You will need:

• 1 x Touch Board
• 1 x Touch Board Proto Shield
• Female and male pin headers
• Soldering equipment

The Proto Shield’s functions

The Proto Shield is simple yet super effective, and we want to give you a quick run down on its design.

If you look at the first image on the right, you can see that the standard Arduino pins have two solder holes instead of one: one hole is for the headers and one for any additional connections. Each pin is labelled by its Touch Board function, so you can quickly get an overview of what is available.

SMD pads

In this image, you should be able to identify an area with 16 lines. You can solder any SMD onto these pads. We have added breakout pins to each pad so that you can easily connect additional components to your SMD. We’ve also expanded the power rails, giving you easy access to the 5V, 3.3V and GND. The GND hole from the Touch Board has been taken into the Proto Shield as well.

Screw Terminals

The image to the right shows the 12 screw terminals. The screw terminal gives you secure access to the touch electrodes. It allows you to quickly attach wires simply by putting them inside the terminal and screwing them tight.

Ground Plane

The ground plane allows you to solder wires to the Shield that are too big for the plated holes, for example, shielded cable strands.

Power and LEDs

Finally, you might be wondering why the Proto Shield has such a strange shape? Quite simple: If you place the Proto Shield on top of the Touch Board, this shape allows for unrestricted access to the power switch, the LEDs, and the reset button.

Preparing the headers

The Proto Shield comes unassembled, so you need to do a bit of soldering to get started.

If you haven’t soldered before, have a look at Sparkfun’s excellent guide. Once you’re ready, it’s time to get your solder equipment out!

To begin, you need to break the male headers into five pieces: 2 pieces with 13 pins, two pieces with eight pins and one piece with six pins. You can use pliers to break off the pieces or carefully snap them apart with your hands.

Check the images to make sure you have all the pieces you need.

Soldering the headers

You then need to solder the female headers to the Touch Board and the male headers to the Proto Shield.

The images on the right show which headers go where on the Touch Board and Proto Shield.

Top tip: If you solder the Proto Shield while placed on top of the Touch Board, as shown here, you ensure that the headers will be straight when attached.

Soldering the screw terminals

Last but not least, you can solder the screw terminals to the Proto Shield. The screw terminals come loose, but like puzzle pieces, you can connect them together.

Simply slide them together as shown on the image on the right. In the end, you should have 12 screw terminals connected in a row. Solder them onto the Proto Shield with the terminal’s holes facing the edge of the Shield.

Create a custom Touch Board project by playing your own audio files

One of the Touch Board’s defining features is to play music, a recording, or a sound when touching the board’s electrodes, acting as an MP3 player, out of the box! The Touch Board comes pre-loaded with an audio guide to help you familiarize yourself with all its features. The audio guide is stored as twelve MP3 files on the board’s microSD card. Changing these files is straightforward. There is no programming required!

The key is to follow the appropriate naming structure for your MP3s to ensure each electrode will trigger the right sound. All you need is a microSD card reader and some great sounds!

You will need:

• 1 x Touch Board
• 1 x USB Micro B to USB A or USB C (depending on your computer’s USB port type)
• 1 x Computer running Mac OS, Windows, or Linux
• 1x MicroSD card reader

Step 1 Prepare the MP3 files

The first step is to select the sounds that you want your Touch Board to play. You may wish to record custom sounds or already have a library of audio to choose from. YouTube is an excellent resource for finding MP3 music (via a download tool) as is freesound.org. Make sure that each file is an MP3 file. If they aren’t in MP3 format, you can always use an online MP3 converter. Note that the file size is important; it takes longer to load if it’s too large.

To use the MP3 files on the Touch Board, you need to rename them. The Touch Board follows a naming structure, where TRACK000.mp3 is for electrode E0, TRACK001.mp3 for E1, and so on, up to TRACK011.mp3 for E11. You’ll see “E0” through “E11” marked on the edge of your Touch Board near the gold electrodes.

In this example, we have two tracks that we want to use: “Bleat.mp3” and “Bluejay.mp3”. We want to use them with the first two electrodes, E0 and E1. So we rename the tracks to TRACK000.mp3 and TRACK001.mp3.

Step 2 Copy the files onto the Touch Board

Take the microSD card out of the Touch Board by pushing it in. It should pop out.

Put it inside the microSD card reader and put the reader inside your computer. The SD card should show up as “TB Audio.” Have a look inside the folder. You will see all multiple files, including the audio files named TRACK000.mp3, TRACK001.mp3, and so on.

Copy-paste the new sounds onto the SD card, simultaneously removing the old TRACK000.mp3, TRACK001.mp3. Don’t worry. Once you have finished copying the files, remove the SD card from your computer.

Step 3 Test the new tracks

Pop the microSD card back into the Touch Board, connect some speakers or headphones to the Touch Board, and turn the Touch Board back on. Try touching electrode E0 and E1. You should hear the new track for each electrode!

Step 4 Next steps

Now that you know how to change the audio file for each electrode on the Touch Board, you can get creative and connect all sorts of conductive materials to the Touch Board’s electrodes. You can use Electric Paint to paint your very own sensors and give an audiobook a new interpretation.

If you want to edit a music file, we recommend the app Audacity. You can use it to trim and adjust the amplitude of a file.

Use Electric Paint to cold solder your board onto almost any material

Cold soldering is an excellent alternative to soldering and doesn’t require a soldering iron or soldering station. Instead, all you need is some Electric Paint! This tutorial demonstrates how to cold solder with our electrodes stencil and the Touch Board and shows you how to cold solder onto other materials!

We also provide a template to easily print out the pitch of the Touch Board or Pi Cap’s electrodes.

You will need:

• 1 x Touch Board
• Electric Paint 10ml, 50ml or 1l

Touch Board electrode spacing

If you want to connect to a number of sensors printed or painted onto a surface, getting the spacing between the sensors is important. If you bridge between the two sensors (because your painted lines are too wide or mis-aligned) those sensors won’t function. Don’t worry! You won’t break your board. It just won’t register anything until the electrical connection between those two electrodes is broken. If you’ve smudged Electric Paint across the electrodes, no problem. Just clean with soap and water.

You can paint your own lines, but to make things easier, we have also designed a stencil, which you can download here. If you don’t know how to prepare the stencil, you can follow our stencil tutorial to learn how to do this.

Once the stencil is ready, align your Touch Board to the Electric Paint traces you have applied.

Step 2 Cold solder

To cold solder, all you have to do is carefully squeeze a droplet of Electric Paint into each electrode that you want to connect to the paint beneath. When you are done, leave the paint to dry. The Electric Paint will act as a conductor and as a glue. That’s it, that’s how you cold solder!

Step 3 drying

Be careful not to move the Touch Board while drying. Otherwise, you risk smudging the paint and shorting the electrodes. Shorting the electrodes will not break the board, but you will need to clean it before you can use it again.

Step 4 Cold solder onto other materials

You can cold solder with Electric Paint to paper and onto other materials, for example, copper tape. This is useful for quick prototyping or when you need to securely attach your board to other conductors.