How to Make Mini Fridge at Home

by ROBO HUB in Circuits > Electronics

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How to Make Mini Fridge at Home

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Hey Friends in this instructable we will see how to make a mini-fridge at home in a very easy way, you need only a few simple materials to make this and I have given very detailed instructions so that anyone can follow.

Before getting started let me give an overview of what a fridge is and how it works.

What is a Fridge?

It is equipment found in every household to keep the food fresh and your favorite drinks cold and it works with a very simple principle.

Before beginning to build our project let me tell you how a conventional/normal fridge works.

Most of the modern-day fridges work on the principle where a continuous flow of refrigerant is done in a closed space causing the temperature to cool down.

The most common Refrigerants used are hydrofluorocarbons (HFCs) and these are the major cause of ozone layer damage! Yes, this is the situation which nobody is willing to discuss, Anyway, let's come back to the version of the refrigerator which we are going to build.

Our version does not use any kind of refrigerant/coolant to keep your drinks cool instead we are using the Peltier module which is available at a very low-cost price.

How a Peltier works

Whenever a voltage is given across joined conductors it will start generating an electric current and due to this heat is produced at one end and hence the cooling starts on the other end, This effect is utilized in the working of our fridge..


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Supplies

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Here are the list of materials you will need to make this

  • MDF Piece of wood 10*11 inch, 11*6.5 inch, 10*6.5inch
  • Peltier module
  • 12v 50A SMPS for power supply
  • Small PC fan
  • Digital thermometer
  • Fan with Heatsink
  • ARGB LED light with remote
  • Neodymium Magnets
  • Thermal paste
  • Thermocol
  • Glue for sticking
  • Hinges for window
  • Acrylic sheets
  • Screws as per the size of hinge brackets
  • Drinks Drinks!

Building Frame

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Start by joining pieces of the same sizes so that we have the shape of the square as in the images, The reason for specific measured installation is we have other components that goes in the box.

Note that if you use the same size of components you can follow these steps, if it's smaller it's good too! but if it's bigger I would recommend having a proper frame making as per your size.

Note: 12V battery was added to get a proper side angle between MDF wood sheets while gluing..

In the majority of the cases, these sizes work, start by gluing them together with glue, I suggest not to use hot glue as it leaves residues if the coupling doesn't go well.

Adding Heatsink

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After our first base frame is ready we can make place for the heatsink and the Peltier module.

Start by tracing the line taking the outer frame reference of the heatsink, we are using the heatsink here to remove the excess heat and provide enough supply of air using a PC fan to the heat sink fins.

These are made of aluminum which is a very good conductor of heat which means they can heat and cool very quickly compared to other metals.

Once we have the traces ready just cut those extra and fit the heatsink. Fin part of the heatsink will connect with pc fan module so that air flows directly over it.

As per the space provided by the heatsink manufacturers attach it to the frame using screws, Now the back layer of the heatsink needs thermal paste to which we will add the hot side of the peltier later.

Adding Peltier Module

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Taking reference of the image tutorials above take care of the electronics which are to be added in the dedicated places.

From the previous step, we have a vacant space with thermal paste applied that will be connected with the hot side of peltier. Fix it with screws so that they do not come out.

Not the colder part of Peltier will be connected to a suction fan that will supply cold air inside the closed cabin( in our case the fridge inside part).

Once this part is complete we are almost ready with building the main part of this project, Now you can encase with the wooden frame which was left out earlier.

Adding Lights

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This is a bonus step to make our project more appealing, Normal white LED strip lights also work but I used an ARGB light with remote control.

The purpose was with ARGB we have control of light colors so that we can change as per the needs accordingly

I added a dc power supply module so that we have steady 5v power for our ARGB light whenever the fridge is turned on.

You can add the strip to the inside of the fridge as in the images.

Building and Adding Door

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I used a piece of acrylic sheet so that we can always have a look at what's inside the fridge, You can easily find this in any local electronic shop.

To attach this to the main body of the fridge and also to make it openable and closable like the doors we need a hinge.

I found these mini hinges super handy with this project, just add them to the sides of the acrylic frame and directly add them to the fridge body.

A small aluminum handle was glued to the acrylic frame(door) that helps in opening and closing.

To make the door attached to the body and prevent any air leaks I used 2 neodymium magnets, one goes with the door and the other with the closing point where this door hits the main frame.

Also to get the live readings of temperature I found a mini digital thermometer that was also added inside and attached to the door.

Finishing

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One last thing that was left is to make this device run continuously like the conventional fridges, So I will be using this SMPS unit, Just connect wires to op side of SMPS, AC input will be connected to input power supply side of smps

Once we have this ready we can close it inside and leave just the wire out so that project looks tidy, Indeed it is!!

Finally you can turn on the fridge keep some of your favorite drinks inside and close the door, wait for around 30mins to see the desirable results.

Meanwhile you can change the colors of the lights and check the reading of temperature on the thermometer.

Hope you enjoyed this idea, if you did don't forget to support us with your likes and shares


Video Tutorial

How to Make a DIY Mini Fridge at Home

Watch this video that shows how our mini-fridge works