Need some Incubator advice - Controlling CPU fan speed.

I am working on a new homemade incubator. I've got everything going pretty good. But I would like to have the option of slowing down the computer fan I've rigged into it. Ive looked into dimmers(heard this is a No-No for fan speeds), rheostats(cant seem to find anyone that sells them in Toronto Ontario, CAN.) Im just wondering how everyone manages?

Any input is appreciated.

Why would you want to slow down the fan?

I currently have a 12V 300mA CPU fan running(mounted inside my cooler incubator). It is powered by a 120vAC 5vDC cellphone charger. Even under powered the fan is pretty noisey and blowing excess air than needed. That is why I would like to slow down the speed.


I have found a 3watt rheostat at The Source.

http://www.thesource.ca/estore/produ...roduct=2710265

Im not sure if thats exactly what I need. I am googling as much as I can, but there is so much info out there and its all headed in different directions. If anyone can chime in feel free to do so :) .

Why not just buy a smaller fan from radio shack, they are rather inexpensive

Quote:

---

Originally Posted by llovelace

Why not just buy a smaller fan from radio shack, they are rather inexpensive

---

Could you recommend one that is small enough, not very powerful(and/or has speed control), and can be mounted?

Couldn't find any that fit the bill.

Lots of people use cpu fans. Im just wondering how :rolleye2:

There has got to be a few people out there that didn't accept one speed for their fan as an option and took it to the next level!

check out the DIY section for incubator builds, there is tons of information there, about types and how to wire.

Ive searched through many stickies and regular threads. None go into detail about fan control. Most just say "slap wires together and presto fan works" more or less.

So, Ill make it my mission. To figure out how to jerry-rig a CPU fan with some control to it. Im sure there's more than a few people on here who can benefit from it. :gj:

Quote:

---

Originally Posted by llovelace

Why would you want to slow down the fan?

---

Because the fan speed has everything to do with how stable the temperatures are shelf to shelf, that and our fan is a lot larger bathroom ceiling fan and had to be slowed down.
If the fan runs too fast it makes the bottom of the incubator hotter than the top :P

Micro-managing the fan lets me dial in all 3 shelves to the same temperature.
We fought shelf to shelf temperature differences until plugging the fan into a rheostat.

Our incubator is a 24 cubic ft. true cooler and for now we use 3 shelves that will hold six 7qt tubs. To get the same temperatures on all three shelves we just move the fan speed up and down until the temps are equal on all shelves.

Bathroom ceiling fan plugged right into a zoo-med rheostat facing backwards to blow against the back of the inc.
http://i968.photobucket.com/albums/a...s/PICT5483.jpg

Sorry, I do not know how to do the same with a computer fan :rolleye2:

I know, he said computer fan Jerry, but I can see why you had to dial back the fart fan

buy a fan with less cfm