Real Life Coin Block




Introduction: Real Life Coin Block

About: Robots and video games...

Do you love Mario Bros?
Did you always want to know how getting a coin by hitting a block feels?
Or maybe you just want a cool place to store your coins.
Well this is the perfect project for you!

Step 1: Materials

The main items you will need are the coins, I used the coins of my country. Any size would be good, but the bigger the better. Cardboard is also important in this project, almost everything is made using 3mm cardboard. For the sound I used an old 128mb MP3 player. A servo hacked for continuous rotation. If you buy a new servo, it will probably come with a few handles, I you use a old servo you will have to make your own handle. Two springs, one to push the coins up, and another to push the coins into the charger. A small piece of a thin plastic, like the kind used in credit cards. Electronic stuff is detailed in step 10.

Step 2: How Does It Work

First we have a stack of coins in a tube. A spring pushes them forward. Then a plastic lever grabs them one by one. The servo moves the lever down. And releases it making it push the coin up. It is controlled by a timer (based on a 555) that fires with each hit to the block. The timer must be configured to make the cursor of the servo turn 360 degrees. Also parallel to the timer button is the play button. So you will hear the sound of the coin every time you press it.

Step 3: Prepare the Mp3 Player

Easy step, open your mp3 player and find the play button, solder two wires to it and then solder a switch to this wires, in order to make an extension of the play button.
You have to make an empty folder with just the sound of the coin, so each time you press the button you heard the sound of the coin.

Step 4: Electronic Boards

The two circuits were made on separate boards.
One is used as a timer. Is responsible for making the servo rotate 360 degrees each time it activates.
The second is an amplifier. It is used to listen to the mp3 player sound on a common speaker. The two boards work on 4.8 volts from rechargeable batteries.

1 - NE555
1 - 100nf capacitor
2 - 1k resistors
1 - 470uf capacitor
1 - tip41c transistor
1 - 10k preset

1 - LM386
2 - 100nf capacitor
1 - 100uf capacitor
1 - 10uf capacitor
1 - 10k resistor.
1 - 1k reistor.

You can find the pdf file for making this boards in the intro step, or just use a perfboard.

Step 5: Coin Tube

Finding a cardboard tube for the perfect size of the coins can be hard, so we are making our own cardboard tube.
Take some coins and tape them together. Cover the half of a paper with glue and roll the coins there.
Then repeat this with a few more papers. When the glue is dry cut about 50mm of the center of this tube.

Step 6:

Another easy step. The credit card plastic should be cut like in the follow image. The size is 78mm x 18 mm.
If you have to make a handle for the servo make it 38mm long.

Step 7: Prepare the Top

The top of the box is the main piece of it. It is where almost everything is attached. Be sure that the hole for the coin is big enough for a coin but small enough that it won't let two coins out at the same time. Use the image as a guide for cutting your shapes. Glue everything and let it dry.

Step 8: Inside

Now install the servo and its handle. Attach the the leveler, with a nut and a bolt.
Then secure the spring with a piece of wire.
Paste the tube for the coins in front of the hole and secure it with some pieces of cardboard. Now you can test if everything is going to work.
The next videos will show you how to test it.

Step 9: Assemble the Box

The box is made of 3mm cardboard and an external measurement of 120 mm.
It can be made larger but you would have to enlarge the images of the sides.
Paste guides to 3mm from the top. These guides will provide support for the cover, which is not glued.
The back is open, you only have two guides for the sliding mechanism (see step 11).

Step 10: Decorate

Print the pictures and glue them to the sides of the box.
The design can be modified, assuming that the sides are of bricks or question mark.
Color the edge of the cardboard with a black marker.
The pdf files for these pictures can be found in step 1.

Step 11: Slider

The slide mechanism is what allows the box to go up and down.
It has to be firmly secured to the wall. It will also be the support for the timer switch and play switch.
The next pictures will show you how to do it.

Step 12: Finish

Use hot melt glue to attach the switches to the sliding mechanism.
Put everything inside the box. Only the battery and speaker are attached, other things can be loose.
Put the back of the box on before securing it to the wall to test if the box can go up and down. challenge

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    7 years ago on Introduction

    I know I'm reviving an old post, but I'm almost done doing this project on an Ardunio. The only reason I'm using an Ardunio is I don't have a MP3 player that will work as easily.

    Anyway, I have all the electronics in place, but I don't know how to get the servo to stop in the same place every time. I'm considering a stepper motor, but I don't know if it will have enough torque. Also I think using a stepper motor will make it hard to use batteries for this project.

    Please help. I'm trying to get this done for my son's birthday in July.


    Reply 7 years ago on Introduction

    it is a servo hacked for working as a regular dc motor. You have to make a timer and make it spin for a limited time. That time is setted by the potentiometer on the 555, Im sure you can make something similar with arduino.

    hi could you let me know how much all the materials cost? thanks!

    hi pudiste dejar que me haga saber lo mucho que todos los costes materiales? gracias!


    8 years ago on Introduction

    does anyone have an estimate on how much cardboard is needed for this?


    9 years ago on Introduction

    Wow! That is an awesome project! One question though, where can I get 3mm cardboard?


    8 years ago on Introduction

    Really cool, but how does it know when you've punched it?


    Reply 8 years ago on Introduction

    look at the switches in the final step


    9 years ago on Introduction

    Holy shignizzle, this is amazing! The next thing would be to make it light up for a few seconds haha.

    tool box
    tool box

    9 years ago on Step 2

    Soy puchacho, De Taringa, Buenisimo tu sistema.
    I´ Am Puchacho, From Taringa, Good sistem.


    9 years ago on Step 12

    I would LOVE to make one of these! and i have read most everything and think i can do it. but i dont get what to do with the things in pictures 10 through 14. could you help me please?


    9 years ago on Introduction

    Hey, i would love you to add this to my group! Great job!

    Here's the link if you want to check it out:


    9 years ago on Introduction

    can you make one that is tougher and less sensitive? I have a power level of over 9000 and it's hard not to destroy things.

    Shadow Of Intent
    Shadow Of Intent

    9 years ago on Step 8

    If the "stop" point of the motor were slightly further round, you could reduce the delay between hitting the botom of the box and the coin coming out. May require a one way ratchet system to avoid the spring trying to pull the arm back again. Excellent job!