Build Your Own Hotplate





Introduction: Build Your Own Hotplate

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Here's a situation, so your driving down the road and being you, you get distracted by the beautiful scenery. As a result of this you realize they you forgot to stop at the gas station on your way home from a long trip. You Run out of gas and as it slowly gets darker you realise that the nearest town is 20 miles away. It becomes apparent that you will need to survive until help arrives. How will you get food? How will you purify water?

Here's another situation, it's nearing the end of the semester and you need to study for finals. You sit down, fueling your little study session is a nice hot cup of coffee. Halfway through your coffee gets cold and gross tasting. What are you going to do, waste precious study time to make more while dumping out the old stuff

Both those situations can be solved with a simple, portable, and effective tool that is a must have for anyone who may need something heated up at any given time.

anders625 here with another DIY project that is as much fun to build as it is useful. This project requires some items that you must purchase off the internet, I will add links for those so you won't need to search vigorously for.

I hope you like this one, be sure to subscribe to me for many more instructables like this one coming soon, also if you like this then be sure to favorite it. If you have any questions or comments then be sure to leave them below, I'm very good at responding and if I don't right away then just be patient and I will respond to you soon. Please be sure to vote for me, thank you.

Step 1: Tools and Materials

Here's what you need:

  1. Thin sheet metal, this will make the body of our hot plate. The metal can be purchased at your local hardware store.
  2. A 9volt battery and a 9volt battery clip for power and to make it portable.
  3. A 10k risistor
  4. A red and blue LED (optional, only serves as an indicator light and to make it look cool)
  5. Potentiometer (this will be used to vary the temperature, but if you don't want to vary the temp then you can cut out the potentiometer)
  6. A switch to turn the circuit on and off
  7. A breadboard with jumper wires (this is optional and is only needed if you want to test the circuit before you make it)
  8. You will also need paper and a pencil for designing the case.
  9. Glue that can stand extreme temperatures
  10. The most important item you will need I called a Peltir thermo electric cooler and can be found here on Amazon.
  11. Wire


  1. Soldering iron
  2. Solder
  3. Tin snips for cutting the sheet metal
  4. And wire cutters

Step 2: Designing the Case

here I have my design for the case. in the first image I have put measurements on one of every line and the lengths of the others are determined by tick marks shone. The second image I choose not to right the dimensions because I was hoping the first image would be enough to give you an idea on the size. The first image is the lid and the second image is the body (in case you haven't figured that out all ready).

Step 3: Paper Template

next you will need to cut out the paper design and put it together to make sure that every thing is up to spec.

Step 4: Paper Model

wow, it looks even better then I could have ever imagined. This is how mine looked, if it doesn't look good don't worry this isn't the final product. After all If at first you don't succeed try, try again.

Step 5: Drawing on the Metal

in this step we will be tracing the final paper design onto the sheet metal. I found that it is easier to hold the paper down with tape while tracing, also be sure not to rub the pencil marks because this will remove them.

Step 6: Cut Out the Metal

now you can cut out the metal using the tin snips. Be sure to wear gloves and googles as the metal can be sharp.

Step 7: Form Box

now in this step we will fold and glue all the tabs to complete the casing. You can use tape as a clamp to hold everything in place while you glue.

Step 8:

this is what it should look like when it's done.

Step 9: Building the Circuit

Here is the circuit on a breadboard to give you an idea of what it's supposed to looks like if you do decide to test it. I also drew up a scamatic for you to look at.

Step 10: The Cooler

In this step we will glue on the cooler using the high temperature resilient glue. I would like to also tell you about the awesome abilities of the coolers, when electricity is applied to them they do two Things. On one side they produce a ton of heat. On the other side the they produce extreme heat, in fact these are used in refrigerators to produce that cool temperature that I'm sure we all know. Another cool thing that these things do is produce electricity. Hold a flame to the hot side and it will produce about 6v of electricity, and hold an ice cube to the cold side and you guessed it, it will also produce electricity.

Step 11: Carbon!!!!!!

now because I love carbon I decided to put a big C on the side, and on another side I cut a holes for the switch and the potentiometer.

Step 12: Building the Electronics

now we will build the circuit. Start by soldering the switch to the positive side of the battery clip.

Step 13:

Now add the potentiometer to the switch.

Step 14:

Take the LEDs and solder them together through a wire, then on the one positive LED pin that dosent have a wire add the 10k ohm risistor.

Step 15:

on the spot where the potentiometer connects to the switch, solder the 10k risistor to it so the leds can light up when the switch is turned on, and solder the other end of the LED wire to ground.

Step 16:

now solder the positive end of the cooler to the potentiometer ant the negative end to ground.

Step 17:

now take some tape and cover up all the connections so the circuit dosent short out.

Step 18: Now Your Done

now put everything in and secure all the pieces with glue and you're done. Now when life throws the cold your way you are better prepared.

I hope you like this one, be sure to subscribe to me for many more instructables like this one coming soon, also if you like this then be sure to favorite it. If you have any questions or comments then be sure to leave them below, I'm very good at responding and if I don't right away then just be patient and I will respond to you soon. Please be sure to vote for me, thank you.



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    We have a be nice policy.
    Please be positive and constructive.




    can you please tell me the theory and the working principles behind this hotplate

    How did you decide the dimensions of the box? and secondly what is the overall cost of this plate?

    I respect your respect for carbon.

    I respect your respect for my respect for carbon. Thanks for leaving a comment.

    I respect ruagaqbuw's "lol" for the respect of respecting the respect of carbon...

    this is a great way to start a fire.

    you'll burn up the potentiometer long before you get to boiling temperature. you might want to use a pwm driver on a higher current source such as the car battery to run this.

    Just for the hell of it im going to make a REAL instructable on a REAL peltier hot plate, i was planning on making a heater/cooler eventually anyway.

    Ill show exactly how the physics behind it work and exactly what is needed to boil water, and in general base everything on actual physics and truth.

    I seriously hope you consider altering your guide and remove the lies that this boiled water. I would even go so far as to call you out to upload a timelapse video of your device bringing water from room temp to boiling temp, with a thermometer in the picture to show the temp over time. It would be impossible no doubt without defying the laws of space-time.

    2 pieces of advice you missed.
    1, unless its a lithium, and/or your cup is made of highly conductive material it would take hours to heat water up. maintaining tempurature however it most certainly could do off a couple watt power supply, but realistically, given a 9v battery has less energy than your typical AA, this wont even warm water up.
    Second, your peltier wires should NEVER be allowed to bend. peltier plates are ceramic and stupidly designed. it is soldered directly to ceramic semiconductors and levers on the corners of the plate, for the first centimeter at least the wires need to be glued flat, parallel to the plate, otherwise it will break which is bad, it creates allot of resistance and can cause the nearby wiring to burn.

    If you changed this to allow connection to some 10w+ power supply then it would certainly be going somewhere