interfaceBoard adventure update

A project log for ramanPi - Raman Spectrometer

The open source 3D Printable Raman Spectrometer using a RaspberryPi and easy to find off the shelf components..

fl@C@ 08/07/2014 at 10:520 Comments

So, after yesterdays tragedy... I started a new day and decided to just try replacing the questionable cap that I repurposed from another board.. Magic.. Everything worked like nothing ever happened. So.. I'm going to re-examine my choice of parts, etc..

At any rate.. Since it was working again, I had the opportunity to spend some time working on other parts.. And so......

The buttons.. I'm putting together a little how-to here.. I haven't seen this done before.. and I wasn't sure it'd work when it came to mind..and I've kinda had it in the back of my mind the whole time with this project..I designed the 3d printable parts like I already knew it'd work...and it a champ.

So, here's what it looks like..

And.. the buttons backlit by the neoPixel RGB LEDs... They are really hard to photograph...!

This is a really quickly thrown together test example.. I made this panel from the lens out of an imax 3d pair of glasses....(I couldn't find any dark plastic laying around so I will have to buy some...)  But it works..

So.. to make a touch sensitive panel like this...

You're going to need something like a silhoutte Cameo or other hobby vinyl/craft cutter.. I use mine for A LOT of things..  If you don't have one.....and can't buy or borrow one...  I'll upload a printable template for the keypad that you can trace and cut by hand...or I am also looking into actually etching the keypad on a single sided PCB and letting the light shine through that.. More to come there, but for now.....

This guide is going to be updated probably fairly soon.. I just wanted to get this up and show how it works and the progress I made..  

1. Get yourself some aluminum tape... They sell it at Home Depot, Lowes, or other hardware stores... Here it is on It's best to get the 3" stuff... If you don't already have this, you should :)

2. Cut a section of the tape about 7 inches or 18cm long..  

3. Place the cut section on the Cameo's cutting the upper left hand corner aligned with the file..about 1 inch down and .75 inches over..

4. Press the cut section and make sure it's adhered to the matt well and is smooth..

5. Place the mat with the cut section into the Cameo (or other hobby cutter)...and load it...

6. With the file loaded in the Cameo software... choose these settings... 

7. Start the cut... and make sure it doesn't bind up in case you didn't flatten it out properly..

8. The cameo will do its business...

9. When it has finished... You'll have the start of the panel buttons!

10. Next you will need to remove the inside of the button icons... and place them on the plastic... Make sure to align them better than I did here...and press them on so they are smooth..

11. When you've got them on.. take a tiny section of copper tape and stick it on the corner of each button and press it on firmly so you have a solder pad to which you can solder the electrode wire...

12. Solder your wires to each button (I only have four in these pictures...)

13. Place the button panel in the faceplate...  (So, again.. this is my test panel... and it's stuck on with electrical tape for the moment.. I need to find some suitable plastic to use to cover the whole face.. but this worked for a nice test.)

14. Wire up the neoPixel RGB LEDs...

15. Power it all up!

And it works!

So, here's the board with the display panel and neoPixel ring...

And a closeup of the board.... The sparkfun MPR121 and level shifter are going to be ripped off the board and replaced with a new adafruit breakout that has the 3.3v regulator and the level shifter all in one breakout... That should be here Friday..

And since I'm not able to go to Defcon, I'll be working on that instead.. :(

It still needs a little work.. But this is a great proof of concept...!