PC Fans for Small Cabinet

[d33p]

After trying to find something small enough to fit my fridge box I decided to stop being lazy and make something that would work for my needs. Mostly constructed from things I had laying around in the garage. Some old 80mm tsunami pc fans, old rocker switch, some wire, and a 12v power supply from an external sata hd kit. Soldered it all together on a circuit board, used inline 3.5 mm headphone jacks to connect the fans (makes them easy to move around and install.



These fans are being used instead of an oscillating fan as I have not found any fans that will fit inside my box. These are just for internal air flow, I do have a large blower fan installed in the top of the box with passive intake. (Temps sitting at 75-80)

 

[JohnnySocko]

timely .... but in so far as the transformer thingy goes, what specs/votage/amps does it need to be? numerous inquiries into pc fans and I've yet to fully understand how to hook that thing up, or is it really that broad of a thing in that almost any of those work (or should I cop one specifically for lap tops)?

 

[d33p]

I used a power pack that was meant to run a SATA hard drive externally. My logic behind this was the fact that pc fans and hard drives run off of the same cabling in a PC. It has 5v and 12v cabelling, I used the 12v to make my fans run at max speed. I bench tested this unit for 3 days and checked it numerous times threw out the day to make sure nothing was heating up. I will be installing them in my box today after work.

For the most part though, every PC fan has a rating on the back and should be ran at those specs or lower. Some are different, but the fan usually tells you Amps and Volts. I used to buy universal power packs that allow you to switch from 3v all the way up to 12v. I prefer these because you can lower the voltage to the fan for speed regulation. I've tinkered a lot with these kinds of things and if you're not comfortable with electricity its not a good idea to create something like this and stick it in a place with water/heat. Home made products like this have a higher failure rate IMO and should be used with caution. If you're looking to do something similar it is a good idea to look up fan modding for PC's. Thats where I started 10+ years ago when mods were less main stream. From there I went on to reading some electronics for newbie's books and a book on soldering techniques. Also bought a couple "bread board" project kits along the way.

Be safe, and good luck!

 

[d33p]

JohnnySocko, one more thing on the "should i cop one specifically for lap tops". Absolutely not! Laptop power packs are usually way higher volt/amp rating than a pc fan could handle.

This is basically the kit I robbed my power from, and with the right molex adapters...you could literally hook a fan directly to it with no modding. This basically gives you a 4 pin molex power supply.

http://www.newegg.com/Product/Product.aspx?Item=9SIA1ZZ0PG3572

 

[polyarcturus]

they will work fine for internal airflow. albeit if you have enough air swapping in and out of grow chanmber they aren't really needed I have ran rooms and cabs both without internal air movement but the air exchange inside grow area was under 1min when doing that.

 

[polyarcturus]

JohnnySocko, one more thing on the "should i cop one specifically for lap tops". Absolutely not! Laptop power packs are usually way higher volt/amp rating than a pc fan could handle.

This is basically the kit I robbed my power from, and with the right molex adapters...you could literally hook a fan directly to it with no modding. This basically gives you a 4 pin molex power supply.

http://www.newegg.com/Product/Product.aspx?Item=9SIA1ZZ0PG3572

I like using old phone chargers

 

[d33p]

they will work fine for internal airflow. albeit if you have enough air swapping in and out of grow chanmber they aren't really needed I have ran rooms and cabs both without internal air movement but the air exchange inside grow area was under 1min when doing that.

I'm about 1 month in without any fans and my plants could not have thicker stalks. My air exchange is pretty ridiculous. In the multiple times a minute range. I did the math originally and found that I only needed an 80cfm fan for my box, however with carbon filter and passive intake...im using a 4" blower fan at 165cfm. My box pulls air from inside my house and has never gone above 80F or below 70F.