Desk Fan/heater




The fan gives you coolness on a hot summer day.  The heater inside provides you with a warm breeze in those cold winter months. This fan/heater comes with a ambient led indicator:  cold=blue, warm=purple. The fan speed and the amount of warmth can be fine-tuned.
As an extra it is suitable for extracting harmful solder fumes. Replace those bulky desk fans with this smaller more convenient fan.

The total cost of the desk fan/heater =  7 dollar. The only part I bought was the PWM dimmer, all the other parts were laying around in my garage.

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Step 1: Materials and Tools


  • Power Jack
  • Spring
  • Turning knob
  • Wooden board 9mm thick
  • Wooden stick 12mm in diameter
  • Switch
  • Computer fan 12v
  • PWM dimmer
  • RGB led strip
  • Power supply 12v 3amps minimum
  • Electric wires
  • Copper rods 10cm long 1,5mm thick


  • Super glue
  • Wood glue
  • Wood wax
  • Jig saw
  • Sand paper
  • Wood clamps
  • Drill
  • Drill bit  5mm, 6mm, 7mm, 12mm
  • Hole saw 90mm
  • Solder
  • Solder iron

Step 2: Sawing

The final product will be a cube. The wood I used is 9mm thick so every measurement is made keeping the thickness of the wood in mind.

Saw 2 squares of 12x12cm, 3 squares of 10,2x10,2cm and 2 rectangles of 10,2x12cm, 4 little rectangles of 1x1,5 cm.

Saw 2 pieces of 3cm from a wooden stick (12mm in diameter).

Step 3: Drilling

I made a drawing of the ventilation holes in Sketch Up, which you can download below. Glue these drawings on the two 12x12cm pieces and drill the circles out using a 12mm drill bit.

Drill a  hole (7mm in diameter) 2,5 cm from the side of one 10,2x10,2cm piece

Drill two 7mm holes 2,5cm from the side of another 10,2x10,2cm piece, leaving at least 2,5 cm of space between these two holes.

Drill a 9cm hole in the middle of the last 10,2x10,2cm piece and drill a 5mm hole on the side (for putting through a cable).

Drill a 5mm hole in the middle of each 1x1,5 cm piece.

Drill two 12mm holes on the  long side of a 10,2x12cm piece 1,2 cm from the side and 7cm from each other.

Step 4: Gluing

Glue two 10,2x10,2cm pieces (square angled) to one 10,2x12cm piece.

Glue the 10,2x10,2cm piece with the 9cm hole in the middle between the two other 10,2x10,2cm pieces approximately 3cm from one side.

Glue the last 10,2x12cm piece on top of the 10,2x10,2cm pieces.

Glue the two 3cm pieces into the 12cm holes of the 10,2x12cm piece.

Step 5: Heating

The heating is done by a spring stretched between two copper rods.

Don’t just use any spring but measure the amperage first by applying a heavy 12v source and a multimeter.  My spring drew about 2,5 amps so it will produce about 30watt of heat at 12v . Well 30watt is not a lot, it will not heat up a room. But it will give me a warm stream of air on me while working on my desk.

Solder the spring between  two 10cm copper rods.

Put the four 1x1,5cm wooden pieces on each end of the rods. Glue these pieces in the corners of the so far wooden box in front of 10,2x10,2cm piece with the 9cm hole.

Solder a cable on each copper rod.

Glue one 12x12cm piece in front of the box for the spring.

Step 6: Electronics

Solder cables on the positive, blue and red of the RGB led strip and glue it in front of the 1x1,5 pieces. Put the wires through the 5mm hole.

Glue the fan in to the box. Watch the direction of flow indicated on the fan.

Glue the power jack, the switch and the PWM dimmer in place.

Follow the schematics in the picture to connect everything together

If you do this correct the blue led and the fan will start to work while you turn the potentiometer of the dimmer. When you push the switch the red led turns on (together with blue it will be purple), and the spring will become warm. Caution: the spring should never be under tension without the fan turning, otherwise the spring becomes too hot and will burn down.

Glue the last 12x12cm piece on the remaining side.

Step 7: Finishing Touch

Gently sand the whole cube.

As finishing you can apply wood wax.   

Step 8: Enjoy

Well, that’s it. After the hard work making this you can relax and enjoy the gentle breeze of your just made desk fan.



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    73 Discussions


    Question 1 year ago on Introduction

    Hi, I'm sorry if this is too late. I saw your project and it really amazes me. I'm just asking for a consent if I could borrow your idea for my innovation. This invention of yours will just be a part of it but it is not the entire whole. Can I also inquire of its overall specifications? Thank you so much!


    4 years ago on Introduction

    Have you considered using large rectangular ceramic resistors (like those used in a power soak) as your heating elements? Being basically springs enclosed in ceramic (like Calrod stove elements) I think they would be a much safer alternative to a bare spring, esp. in a wooden box with limited airflow and no other safety features (fuses, tip-over switch, thermal liner, etc.). Of course, I also think you should add a few safety features, esp. two fuses, one current, the other thermal eve with the safer resistor.

    2 replies

    Reply 2 years ago

    Good idea. I am a trying to build a heater. I have a 20 watts ceramic resistor but I do not know it's max temp, max volt, max current and resistance. (


    2 years ago

    Wow, Its amazing...

    but if this work on 5V then everybody can use with mobile charger or mobile power bank...

    Actually i also required.

    if any have circuit with 5v please mail me.. (


    2 years ago

    what about using nichrome wire instead of the spring?


    2 years ago

    This is a really cool project, it's going straight to the "to do" list


    Reply 4 years ago

    man is there any way to increase current in TEC1- 12706 .. I used pc 300w power supply 12v which capable to give20amp but peltier takes only 3amp.
    and the other thing to control the temprature on off switch ... i have some thing idea about this but main problen is to draw more current..


    Reply 2 years ago

    A peltier is just a heat pump so you might be able to get a cool stream of air but you'd be dumping heat back in to room + heat from power supply = net loss.


    3 years ago

    A small switch on the underside would be good to shut it off in case it gets knocked over.

    1 reply

    Just use a tilt switch, when it falls over, it breaks the circuit automatically, and also resets itself when placed upright.


    3 years ago

    I am trying to make it, I have a fan that is 12v at 0.15 amps and a spring that when I put power through gets hot but I can't measure the power it draws and if it will work with my 9v at 2amps and 18watts power supply


    3 years ago

    Good job!


    Check it's amp draw, and the voltage it's running at, and calculate the wattage. The internet has plenty of info to calculating wattage.


    4 years ago

    This device is totally illegal in the United States. I can not speak about other countries. It is a fire hazard of the first order. Even if it were not illegal, a wood box for an electric heater is absurd.

    2 replies

    Reply 3 years ago

    Nothing illegal about it, but you probably would not get it certified to sell


    Reply 3 years ago

    How is it "illegal"? What U.S. code does it break?

    In any case, so what? We DIY'ers aren't bound by feel-good legislation that forces us to rely on experts to do our projects for us. Hopefully, we use a bit of common-sense and make things as safe as we can and include safety warnings in our articles, legality be damned....

    I'm just sayin'....