Instructables
Welcome to my first Instructable.  I've had this idea for quite some time but finally got the motivation to put my idea in to production. 

First let me give a little back story / problem.   I have a Dell XPS laptop that gets hot,  Really hot.  I first bought a belkin laptop stand for 20 bucks and the thing still works well its just that it elevates the laptop an inch and a half in the front and almost 3 inches in the back so for extended usage really kills my wrists.

I decided that I could figure out a way to build a fan in to my desk and power it by USB just like my laptop stand and never have to worry about the heat or the bad angle again.

I tried to be as thorough as possible in my instructable but its actually a pretty simple concept that anybody with a few tools could see exactly how I did it with just the pictures and recreate it rather easily.

I hope you enjoy the instructions and if you have any questions please feel free to email me or comment.




Step 1: What you need!

Picture of What you need!
DSCN0569.JPG
ITEMS NEEDED :
1 Rocketfish 120mm case fan (Best Buy, $14)
1 Spare USB cable that you can cut.
1 Desk with enough room underneath to mount.
1 Scrab 1by4 Piece of Wood
4 Wood screws,  Length varies by the thickness of your desk.  Mine were an Inch and half long.


TOOLS NEEDED :
1 Pair of Wire Snips
1 Router or Heavy duty Dremel
1 Table saw of some variety.
1 Drill and Wood Screw
Electrical Tape
Wire Connectors of some sort.  I used this plastic material you cover the wires over and melt down to make a a nice seal.


A few odds and ends, Marker, Piece of Cardboard, Scissors...etc etc.

 
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rronald_252 years ago
I have the same idea of making my own custom laptop fan but I was wondering how can I connect 3 or more fan and power it using wall plug (or wall plug adapter).

The reason why i need more fan is because lately my laptop gets overheat very quick & it forces automatic (sudden shutdown)
leo_kendall2 years ago
I did the same kinda thing. but with a twist.
my laptop lcd was on it's way out. flickering and sometimes not even coming on. Also the battery was shot lasted about 2 min the max. I had a 18.5" lcd monitor so i thought i used that.
I ripped the screen on and decided to keep the power jack in at all time.
i cut a hole in my laptop desk and installed a 80mm 12 volt fan.
i went and purchased a harddrive/dvd rom adapter of ebay for a few bucks. this adapter put out both 12v and 5 volts. i hooked this up to the fan with a switch to run the fan at 12v or 5v. just a flip of the switch can turn the fan on or off, and or 5v or 12v. so when i wants a quite fan i switch it to 5v and when i'm using flash for example i flip it to 12v.
also i ran a few wires from this adapter non switched to a powered usb hub 5 volts, and ran another set of 12v wires to a led strip that shines light on my pull out keyboard.
tylorweaver2 years ago
Why didn't mount it facing the other way, but reverse the polarity of the wiring instead? This way, the fan itself is free of any possible obstructions that might come in contact with the blades, when setting your laptop down on top of it.

(yes, I know all laptops have feet, which would bring the backside of the case, further away from the fan blades... still, why risk it?)

Great first write-up btw.. Enjoy!
Dorien2 years ago
Do you have the fan exhausting downward away from the laptop or does it blow upward against the laptop bottom? In Christ, Dorien
bmarshall-23 years ago
I may have defende you earlier, but I will complain that you went and bought a $14 PWM fan for this project, here in the UK we can get a 120mm fan for about £2 that runs off the 4 pin molex in a PC, even then it only uses two pins, 12v and ground. If you're using a PWM fan with an RPM sensor in it (which you are..) then you could've incorporated a PC fan controller (such as the Zalman MFC-3?) running off a wall-wart, then you could've run 4 fans, 1 of which is PWM AND controlled it's speed precisely (to 60rpm...).

http://www.amazon.com/KingWin-120x120mm-Long-Bearing-CF-012LB/dp/B002YFP8BK/ref=sr_1_7?s=pc&ie=UTF8&qid=1308989235&sr=1-7 ..surely this is a better option, or something like that.

either way, this is a good idea, it could just use a little more development.
bmarshall-23 years ago
All these comments about 12v and 5v, running a 120mm fan off 5v still shifts PLENTY of air, and it keeps it quiet! Most fans won't draw than a watt or two anyway and you get 2.5w from USB. I run fans off USB from time to time as well, and to the guy saying about a DC/DC transormer, you'd be cutting the current down a fair bit with that, you'd have to run it on two (or more) USB ports to get enough current to make that a viable solution.
qwerty1563 years ago
a DC-DC Converter (5v to 12v) to run the fan would be nice.
bsnowman173 years ago
That fan is 12V, usb is 5V with a 500mA current limit. Use a 12V wall adapter to see the fan at its advertised RPM.
Thanks for sharing the idea
it was well explained,simple cheap and save
my almost 10years all laptop which kept
overheating well done best tutorial of this site
thewizard424 years ago
Usb is 5v
i forgot... is it ac or dc?
Dc
Thats what i thought.
timex (author)  thewizard424 years ago
See that shows how much i know.
Great ible though. probably going to do this myself
timex (author)  thewizard424 years ago
Awesome, Let me know how it turns out!
hoey784 years ago
The fan looked like it was turninga bit slow???
zack2474 years ago
looks nice, but i'll have to find a different desk before i do this, can't do it to the main one Great 'ible!