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.

Step 1: Materials and tools

Materials:

• 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

Tools:

• 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

Comments

[Peter880]

UK PWM Fan Controller
http://www.shinyhardware.co.uk/prods/showprod.asp?pid=18732

Cheap and decent, I bought one ages ago.

[Schmidty16]

man i love the look of it i wish i could make one i will try someday

[jdmumper]

I like the look of the wood box. It might be fun to hack in a Peltier heating/cooling element. I have no design to offer, but... Here's an example device that will raise the required current to 6+amps, but might be useable with the proper aluminum fins... http://www.amazon.com/TEC1-12705-Thermoelectric-Peltier-Cooler-40mm/dp/B002UQKEU8/ref=pd_sxp_f_pt

[Spokehedz]

Link to where you bought the PWM dimmer module?

[octochan]

Would this dimmer switch work instead? It isn't labeled as PWM

http://www.ebay.ca/itm/120782777352?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

[HHarry]

It is really a pity my supplier won't ship outside Europe, it is really a good product. If you are just going to use the fan the dimmer you mentioned (I think) will work. But with the heating element installed the dimmer will burn down. You should calculate how much amps all your components need and than buy a proper pwm controller, but don't spend to much money on it. On ebay type pwm controller.  Here is a similar product http://www.ebay.com/itm/12V-40V-24v-36v-3A-Pulse-Width-Modulation-PWM-DC-Motor-Speed-Control-Switch-/110888220149?pt=LH_DefaultDomain_0&hash=item19d173f5f5  

[HHarry]

(removed by author or community request)

[j0npae]

I live in the US and I tried looking for this thing and I cannot find it. Are there any alternatives to this piece?

[HHarry]

http://www.ebay.com/itm/12V-40V-24v-36v-3A-Pulse-Width-Modulation-PWM-DC-Motor-Speed-Control-Switch-/110888220149?pt=LH_DefaultDomain_0&hash=item19d173f5f5

[RankineCycle]

If 30 watts is working for you, that's great. My experience with portable electric heaters is that they are usually rated around 1500 watts, maybe with a "low" setting of 750 or 1000 watts. I've used a ceramic-element heater which, once up to temperature, would settle down to 400 watts on its "low" setting. This was barely enough to keep a small room warm.

[HHarry]

Yes, I know It just gives a warm stream of air nothing more nothing less. Just like I said in step 5.

[rickharris]

I might suggest that some nichrom wire would make a better heater element. The spring is likely to fatigue or just burn out .

I would suggest a sensible fuse in the circuit is a good protective device in case of excessive current.

Is putting a heat source (30 watts is quite a lot) in a wooden case advisable?

[HHarry]

The spring does not burn down; the fan keeps everything cool. You can see it as a hair dryer: 2000 watt in a confined space still the hair dryer does not melt down.
My design is like putting a 30w light bulb in a open wooden box with a fan on it.

But yes nichrom wire would be a better option. Also a tilt switch is advisable so everything shuts down when the box is putt on his back.

[Wroger-Wroger]

Yeah... nice design...

Tilt switch = good

Thermal fuse appropriately located near the resistance heater  = good + necessary.

A way to clean the dust and crap out of it every year or so.... Fluff and dust = fire hazard.

[rickharris]

You have made me happy :-)

All is OK - even with a hair dryer - until the fan stops - ask my wife! :-)

[Lunera]

Hair dryer coils are made of nichrome. You can find the stuff pretty cheaply online if you look. http://jacobs-online.biz/nichrome_wire.htm has a nice calculator for determining how much of what guage you would need for your particular application.

[lime3D]

Just go to Salvation Army and buy and old hair dryer to hack the coils out of it.

[Lunera]

forgot to mention, if you do use nichrome, be EXTREMELY CARFEUL, I just thought about the fact that your enclosure is made of wood.

[MrNickBarker]

Finally, a project that interests me enough to build. Only thing that concerns me is the safety aspect of it. When I build mine I'll put a couple more of safety features in it.

[NightLord]

Well if you want more heating power, just add some more springs in paralell... just be careful it doesn't heat too much.

[scottinnh]

Congratulations on a polished product and documentation.

Your drilling was perfect not just with pattern spacing, but also for smooth bore holes. Wasn't till I saw the close ups that I could tell it wasn't laser cut.

I'd suggest to anyone else that they clamp a piece of sacrificial board to the front faceplate, to avoid splintering when the drill bit punches through.

Other suggestion is to skip the heating element and buy the right sized 12v light bulb... An incandescent bulb is a heater, light, resistor, and safety fuse all in one.

[Spokehedz]

Yeah, but then it is icky nasty incandescent light blasting out of the vent holes and you wouldn't be able to see the LED.

Also with those long power bus bars you could easily add one or two more springs in there to get a little bit more heat blowing through. Plenty of space in there, but obviously the power requirements go up.

GREAT JOB!

[longwinters]

What drew me to your project was the neatly done grill holes, I know it sounds silly but having made a few projects over the years that require evenly spaced holes it's more difficult than you would think. Nice job, if you planned to leave it running while you go on vacation for a month, a thermal cut off fuse is about a buck.

Nice touch with the back lit LED's