Introduction: Stay Cool This Summer: PC Fan Mod

Picture of Stay Cool This Summer: PC Fan Mod

Who does not have a dozen of those PC Fans laying around? In this build I will show you how to use those fans to produce a nice adjustable breeze during hot summer days. And it runs at least 4 hours with an ordinary 9V battery.

Step 1: Watch the Video!

The video gives you a pretty nice overview on how to build this mod. But I am going to give you some extra information in the next steps.

Step 2: Order Your Parts!

Picture of Order Your Parts!

Step 3: Build the Circuit!

Picture of Build the Circuit!

Here is the schematic for the circuit. I recommend to build the circuit on a breadboard first. And then move it over to the sides of the fan. But it is a pretty simple circuit and perfect for beginners.

Step 4: Success!

Picture of Success!

There you go! Now you can refresh yourself pretty easily with only a 9V battery.

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Keiichii FranciscoT (author)2017-03-01

i mimic this projects.. but my power supply is 5volts/power bank... tip29 transistor... 5 volt fan...ceramic cap 2nF and it works excellent! :)

i use different components cuz some of it are not available or out of stock on our local electronics store...

JoãoP94 made it! (author)2016-07-28

Works like a charm ^^

I'm your follower on YouTube. Keep the good work :D

yossef987 (author)2016-05-04

Can i use a Ne555N instead?

jpmorgan34 (author)2015-01-18

I used the same designee and I 3d printed a case for it. Thanks so much for this awesome demo works great

Sorry for such a late request, but could you possibly post the files for the 3d printed case on Thingiverse, or a similar site? That is, if you still have them of course.

dansassin (author)2016-04-22

Something worth noting is that some fans (including the one I tried) have a voltage cutoff point, where it will not spin at all if it is too low. For the fan I used, it happened to be around 8 V before cutting out, which caused a lot if confusion for me.

For simply testing the circuit, I'd suggest hooking it up to a bare motor with no internal circuity.

haroun (author)2014-08-18

Will this work with a 12-14 volt input, ie, in a car?

GreatScottLab (author)haroun2014-08-21


rawat006 (author)GreatScottLab2016-04-08

can NE555 works properly if we use 12V in the same design?

ahmedsidd (author)2016-01-01

pls can you tell how much volts does the 2.2 and 10 nf are??????

SebastianB43 (author)ahmedsidd2016-03-10

they are capacitors not volts.

pradyumna s nadig (author)2016-02-02

greatt Scott u do great videos n I suggest u to do an laser security alarm for your next project so can you do this project for me

theGiallo (author)2015-09-06

Thanks for this instructable! I've learned about the existence of PWMs! :P
I bought this LED dimmer for 3.57€ and tried it out on some PC fans.
The fan slows down, but makes noise, as if the frequency of the PWM was too low. Is it possible?
For now I have no speed regulation. Uh, I'm using a 12V 1A DC power adapter.

GreatScottLab (author)theGiallo2015-09-08

The frequency of the signal is hearable due to the vibrations of the coils of the fan. You would need to increase the frequency. But that is not possible with such a product.

theGiallo (author)GreatScottLab2015-09-08

Hmm. Thanks!

teddy_ho (author)2015-08-19

i think we can use more cheap battery charger AA 1.5v, using dc to dc step up module to get 9v, how about that ??

PedroM9 (author)2015-05-23

Could I use 3.3nF capacitors or even two 1nF capacitors in parallel to use in place of the 2.2 ones?

And also, why is there two positive 9v poles in the circuit? Isn't there just one battery in there? Isn't the ground of the circuit the negative of the battery?

(I know its a pretty dumb question, but hey, there's always a first time for everything" xD)

Mad Fox (author)2014-12-06

somehow it didn't work for me :\ I wasted my entire day, check every connection and it just didn't work

Machine (author)2014-08-03

Why all the electronics? Just connect the 9 Volt battery to the fan. It should run. When the battery runs flat, plug it into the charger.

Here's a suggestion, if I may. A good project might be to make a 9 Volt battery charger in the fan, so that when you plug into a DC supply (like a plug-pack, wall-wart, whatever people call them) you can both run the fan and charge the battery. When the battery is charged up again you can remove the DC supply and move the fan to where ever you like on your desk or bench.

A fan is good when soldering too, to blow away the fumes.

You did a nice project, thanks for showing us.

OhYeahThatGuy81 (author)Machine2014-09-23

>> Why all the electronics? Just connect the 9 Volt battery to the fan. It
should run. When the battery runs flat, plug it into the charger.

Um.... the circuitry allows you to vary the speed of the fan.

Raphango (author)2014-07-23

could you please tell me why did you use PWM (555)? Wasn't enough to use just a potentiometer?

GreatScottLab (author)Raphango2014-07-25

I like this question so much that I am going to make a video about it to answer it properly. You have your answer in one week ;-)

Raphango (author)GreatScottLab2014-07-25

I' really looking forward to watch it!

kag432 (author)2014-07-23

I would burn through batteries so fast with one of those! I would suggest a wall wart from other electronics as a cheaper alternative for those who have them.

gravityisweak (author)kag4322014-07-23

or maybe a solar panel!

kag432 (author)gravityisweak2014-07-23

Not cheap, but certainly cooler (both literally and figuratively).

gravityisweak (author)kag4322014-07-24

True, not cheap. But 9v certainly aren't cheap either, and at least if you're using a fan, the suns probably out.

смитрић (author)2014-07-23

just an old cellphone charger will do

Verticees (author)2014-07-23

Great project!

Jobar007 (author)2014-07-23

I did this a while ago and while it does work, it eats 9v batteries. I found better success using the same circuit (the PWM circuit you have above) with a USB cable instead of a battery. It wasn't as portable, but I was using the fan anyway while on my computer.

jessyratfink (author)2014-07-23

This is a good idea! This would be great for pets too if properly cased :D

About This Instructable




Bio: Awesome Electronics Tutorials, Projects and How To´s
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