Introduction: The Incredible Paper Calculator Mod (Oh My!)

In this howto of howtos, I will demonstrate how to take an ordinary, boring $3 calculator and turn it into a piece of art and give it the potential of limitless self expression.

The final product is more proof-of-concept than practical, but with each version it has gotten more usable.

I was inspired to make this one day in Earth Science a couple of years ago when i took a piece of cardboard and drew a calculator on it and thought, cool.

Sometime in May I decided that I would go right to my room (then sans computer) and get to work on something productive. Instead, I made v1.

Step 1: Materials

1. One appropriately thin, cheap calculator (solar is best)

2. Thin pieces of cardboard. I used the material from the back cover of an old spiral notebook and some other bits of thin cardboard I found lying around my basement.

3. One "faceplate". I followed a 3x5 theme so I used a piece of lined 3x5 notecard with numbers written write on it. You can use whatever you like.

4. Foil for the contacts. I'm thinking about getting some aluminum tape, but is fine.


1. Glue

2. Hobby knife

3. Clean, non-smudgy hands

Step 2: Strip Down Your Calculator

Not much to say here, just be careful about wires. My calculator was incredibly easy to take apart, I only had to peel back some material and undo 6 screws on the board.

Step 3: Cut Out Your Cardboard

As I wanted my calculator to be 3"x5", I just traced a notecard and cut out the pattern. As I've said, you can do whatever size you like. You will need three pieces of cardboard, and one paper-thin faceplate.

The last picture shows the ideal thickness of the cardboard. You'll see why that matters more in a later step.

Step 4: Make Room for the Circuit Board.

This step is important for maintaining the flat profile of your finished product.

Trace out the parts of your calculator's circuit board, screen, and solar panel onto a piece of cardboard (first picture).

Don't worry if the screen or the panel stick up a bit, you can take care of those with the next layer, but if the circuit board is too tall, you'll have to repeat this step with another piece of card.

Step 5: Cut Out the Next Layer.

In my first design, there was no seperation between the foil contacts and the buttons. The calculator would still work, but it could get frustrating. With this new layer I solve that problem.

Cut out a grid in this layer on top of the spaces for the buttons. Make the holes as wide as possible.

Also cut out spaces for the screen and panel.

Use the grid as a template for the spacing on your faceplate.

Step 6: Customize Your Faceplate.

This step is up to you, just make sure you get the spacing right.

Step 7: Add the Foil Contacts

Because we cut out the grid in step 5, all you have to do is paste a rectangle of foil onto the back of your faceplate. When you press a button, it will touch the corresponding button on the circuit board. The grid keeps the buttons nice and separated.

Step 8: Glue Everything Together

First the backing, then the first cut-out piece, then the circuit, then the grid, then the faceplate.

Step 9: Impress Your Math Teacher.

and post your pictures in the comment thread!