Connect Four is such a famous game that most of you must have played it at least once in your life!

I had both the regular and pocket version when I was little and it's one of the games I played the most with. I still have the big one, even though some discs are missing...
The base seems pretty easy to make so I thought I would try to build it using cardboard!
As you can probably notice from my other instructables, I love cardboard because you can do so many different things with it! And let's not forget that recycling (or upcycling, in this case) is very important too.

This Connect Four worked perfectly in my mind and I thought that making it would have been easy...but of course I was wrong! :D
Building it following these instructions will be much easier for you, so don't worry!
The reason why it was so hard for me is because I designed the whole thing in my head only, so I encountered some obstacles that made me think about giving up more than once. But I am stubborn and after a week of trying, here I am! :)

I hope you like it!!

Step 1: What You Need

cardboard
a box cover
newspaper
sheet of paper
hot glue
white glue
acrylic paints/aerosol varnish
scotch tape
velcro

Tools:

ruler
cutter/scissors
pencil
paint brush

Step 2:

Take a box cover. Mine is 20,5 x 30cm (8,07 x 11,81 inches) so the measures written in the next steps will be based on this. In case your box is different, try to adjust the measures.

So let's start diving the box in 2 on its length and trace a line.

My box cover is 3,5cm (1.37 inches) high so cut a 3,5 x 20,6cm rectangle out of cardboard. I used a pretty thick cardboard for this, it is 5mm (0.19 inches) thick.
Glue this piece of cardboard in the middle of your box, on the line you traced previously.

Now, take a thinner cardboard if you can, and cut other 2 pieces exactly like that one, plus 2 bigger rectangles 14,7 x 20,5cm (5.78 x 8.07 inches).

Step 3:

What you have to draw now, is a grid on your 2 biggest rectangles.

Let's start from the border on the longest side.
Using a pencil and a ruler, draw a 9mm (0.35 inches) strip, then a larger one 2,3cm (0.9 inches).
Again, draw the 9mm strip and the 2,3cm one. Continue this way until you reach the other border.

Now you have to do the same on the shortest side of your rectangle, the only difference is that the thinnest strip will be 5mm (0.19 inches) instead.

Once you have your grid, you can notice that you have obtained many squares, created by the largest strips.
So draw a circle in each square but make sure that they fit the squares perfectly. They can be a little smaller but NOT bigger!
Since the squares are 2,3cm large, the circles radius should be 1,15cm (0.45 inches).

Do the same on your other cardboard rectangle and cut all of these circles out...you won't need them anymore!

Step 4:

Take one of the smallest rectangles that you cut previously and place it under one of the grids, leaving about 2mm (0.7 inches) of free space between them.
Join them together using scotch tape, always being careful of leaving a little bit of space between the 2 pieces of cardboard. This way you will be able to bend them (see pictures).

Do the same for the other grid.

Step 5:

Now, always using thin cardboard, cut 7 thin strips long 14,7cm (5.78 inches) and 5mm wide (0.19 inches).
I made it 5mm because that's the thickness of the thick cardboard I used at the beginning.

These strips will divide one of the grids in 6 sections.
So start gluing a strip on the shortest border and one on the other, as you can see in the pictures. Try to glue them as perpendicular to the grid as you can.
You can use hot glue for this, or white glue, it depends on how much patience you have! I used hot glue :D

Glue the remaining 5 strips between each line of circles, exactly like you did for the other 2 strips.

Step 6:

I used a cutter to cut everything, including the circles, and as you can see, they are not perfect at all (and pretty ugly to see).
For this reason, I decided to cover everything with the paper mache technique. This will make everything stronger and smoother.

For this technique all you need is white glue, water and paper.
You can either use newspapers or toilet paper (not kidding!). The result using toilet paper is actually better and stronger in my opinion...but I decided not to waste it and recycle newspapers instead (I have many!).

So take a few pages of newspaper and make many pieces out of it, tearing it off with your hands.
Do the same if you use toilet paper.

Prepare some white glue in a little container and add a little bit of water at a time to it.
Mix everything using a brush until your glue becomes more liquid. Be careful not to make it too liquid otherwise it won't stick anymore! In case you put too much water you can add more glue until it's perfect.

We are going to cover everything with paper mache (all the pieces of cardboard and the box) so let's start spreading some of the glue mix that you prepared on the cardboard, using a brush.
Lay a piece of newspaper on it and spread some other glue on that piece to make it stick to the cardboard.
Cover the whole surface this way and let it dry.

You can make another layer of paper mache to make it harder, it's up to you.

ps: you will probably notice some wrinkles on the paper while doing this: don't worry, they disappear as they dry!

Step 7:

The base of this game is usually blue so I thought I would paint it blue using acrylic paint.
As I started to paint everything in blue, I noticed that the paint wasn't covering the newspaper, as if the color was transparent. So I painted more than one layer to try to cover everything, but I still had that problem...

So, my Connect Four is blue and transparent in the pictures that you will see from now on, but I later decided to use another kind of paint that would cover the newspaper (see Step 9).

In case you used white toilet paper instead of newspapers, you probably won't have this problem and you can use acrylic paints.

Anyway, what you have to do now, is gluing a grid to the rectangle that you placed in the middle of the box at the beginning. The part of the grid that you have to glue is actually the small rectangle that you added later with the scotch tape, the piece that you can bend.
Glue the other grid on the other side and make sure that the part with the 7 strips faces the other grid.
I hope I made this clear enough...take a look at the pictures to fully understand what I mean :)

This way you created 2 "doors" that you can open and close!

Step 8:

I noticed that there was too much space at the bottom of the grids so I decided to add some other strips.

Cut 6 strips out of cardboard 0,5 x 3cm (0.19 x 1.18 inches) and place them between the longer strips on the grid, almost at the bottom, leaving about 2 or 3mm (0.07/0.11 inches) from the last circle.
Use hot glue to secure them and finally paint them too.

Step 9:

As I already anticipated, I had to think of some other kind of paint that would cover the newspaper.
I decided to use aerosol varnish.
The problem here is that I didn't have it in blue so I chose green between the ones I had!

Simply cover the whole base (including the grids) with the varnish and wait for it to dry.
It's pretty fast and covers everything perfectly!

Step 10: Final Touches

In order to be able to play with your game, you need the grids to stay still...

Cut a piece of scotch tape, about 5cm long (1.96 inches).
Fold the 2 long borders to join them together on the sticky side, in the middle of the tape, and press with your fingers.
Now cut this strip in 2 equal pieces.

Cut 4 little pieces of velcro, about as big as half tape strip.
Glue one side of the velcro to one of the ends of the scotch tape strip.
Do the same for both strips.

Keep the other 2 pieces of velcro aside for a minute.

Step 11:

Take one of the strips and glue its free end (the one without the velcro) to the top of one of the grids, between the first and the second circle. The velcro must face the other grid.
Fold the strip so that its velcro reaches the other grid and glue it.
Wait for it to dry completely before trying to open the velcro.

Now do the same on this second grid, on the other side, always between the first and second circle.

Once the glue is dry, you can separate the pieces of velcro to open and close it. This will keep the grids together.

I designed this base in a way that you can also close it when you're not playing, so take another piece of velcro and glue it on the back of the other velcro that is already glued to the strip.
Bend the grid to close it, and glue the other side of the velcro to the side of the box.
Do the same for the other strip.

Step 12: The Discs

To make the discs, draw a circle on cardboard using a compass. The radius of the circle is 1,4cm (0.55 inches).
They must be bigger than the circles you cut previously otherwise they will come out of the holes.

Cut the circle and use the disc you obtained as a guide to draw other 29 discs on cardboard.
Cut all of them too.
They must be 30 discs.

Step 13:

The cardboard I use for this project came from a colored and lucid box so painting the front side with acrylic paints wouldn't have covered it.
For this reason I decided to glue both sides of the discs on paper and cut them out.
This way you have a blank surface you can easily paint on.

Divide your discs in 2 groups (15 on one side and 15 on the other) then paint one of the groups in red and the other in yellow.

Step 14:

The slot your discs will pass from is about 5mm wide (0.19 inches). The discs are not as thick, so they would probably fall next to each other while you are playing.
I thought to make their borders thicker using hot glue: after doing it twice I burned my finger (ouch!) so I decided to do this using the slowest method: white glue!

So take your white glue bottle and pour a thick line of glue all around the border of the discs and let it dry.
Do the same on the other side.

If it still doesn't seem thick enough for you, you can add another layer of glue and let it dry.

Your discs are ready!

Step 15: You're Done!!!

Place your yellow discs in one side of the box, the red discs in the other side and get ready to play! :D

When you are done playing, simply bend the grids and close it!

Enjoy!!!