Results 1 to 12 of 12

Thread: Balancing computer fans

  1. #1
    Join Date
    Jun 2009
    Posts
    936

    Balancing computer fans

    I've read posts on the web that say noisy computer fans can be improved by balancing them. The fans aren't massive, so this is accomplished with bits of tape or dabs of glue. However, I haven't found a systematic description of how to do the balancing. I suppose it's no different than balancing a tire, but the machinery to balance tires is complicated. What method could be applied to computer fans?

  2. #2
    Join Date
    Jun 2009
    Posts
    1,383
    I learned a few things about fans when i was building amplifiers. The first is that you really don't need a lot of air, just a slight breeze. Look at the fan on a laptop or playstation3. Tiny! The second thing i learned is that a 12 volt fan will spin up with 5 volts.

    I used to take a 12 volt fan that was bigger than i needed and use a resistor to give the fan 6 volts. I now have leftover 50 ohm 5 watt resistors for the future.

    Balancing a cheap plastic fan sounds like overkill. It would be more appropriate for a ceiling fan

  3. #3
    Join Date
    May 2009
    Posts
    176
    The easiest way to reduce noise from them is to slow them down, you can use a resister to do this.
    But of course this reduces the airflow.

  4. #4
    Join Date
    Jun 2009
    Posts
    936
    I'm curious about balancing the fans. Slowing them down would make them quieter, but I'm not curious about tackling problems it would cause with the BIOS features that monitor or control fan speeds. I don't want to disable those features.

  5. #5
    Join Date
    May 2006
    Posts
    5,511
    I used to let the computer run all day while I was at work to let long programs run their course, but came home one day to the sound of the fan clattering away. To fix it, I applied a very slight pressure to different spots on the flat part in the middle with my finger while it turned until I found the place that would balance it out, or what made the noise stop. Then I strapped one of those bread tie things across the front of the fan through little holes in the corners of the fan housing with a small wad of paper around the middle of it that would barely brush the spot that had quietened it before. It worked fine for a couple more years like that, but needed adjusting every once in a while when it started to get louder again. Probably better to just bring it to one of those computer repair shops though.

  6. #6
    Join Date
    Jan 2010
    Posts
    4,950
    Quote Originally Posted by tashirosgt View Post
    I've read posts on the web that say noisy computer fans can be improved by balancing them.
    That doesn't seem to work, the Intel and AMD crowds still keep getting into loud flamewars.

  7. #7
    Join Date
    Jun 2003
    Location
    SE Michigan
    Posts
    2,902
    The technique I learned for ceiling fans may be useful. Typically, the weights involved there are only a few (10?) grams. Since you're working with something much smaller, you'll need less. Be prepared to spend some time.

    Start the fan, and note how much noise it makes. (For a ceiling fan, watch the wobble.)
    Apply a small weight to the center of one blade. Start the fan, and note whether it is noisier or quieter (wobbles more or less).
    Move the weight to the next blade start it again, and note the noise (wobble) level.
    Repeat for each blade. Make a note of which blade(s) had the best effect.
    Return the weight to that blade, placing it closer to the hub. Check the noise level. If it's better, move it farther in. If not, move it out. Repeat until (a) you're satisfied or (b) you go crazy.

    Ceiling fans come with a balancing kit, one or two self-adhesive weights and a plastic clip with the same mass. You use the clip to find the best blade and location, and then stick a weight there.

    Fred
    "For shame, gentlemen, pack your evidence a little better against another time."
    -- John Dryden, "The Vindication of The Duke of Guise" 1684

    Earth's sole legacy will be a very slight increase (0.01%) of the solar metallicity.

  8. #8
    Join Date
    Jun 2009
    Posts
    936
    Quote Originally Posted by Nowhere Man View Post
    Ceiling fans come with a balancing kit, one or two self-adhesive weights and a plastic clip with the same mass. You use the clip to find the best blade and location, and then stick a weight there.
    I'm glad you explained that. I've never dealt with ceiling fans. The ceilings in my house are too low for them.

  9. #9
    Join Date
    Mar 2004
    Posts
    17,367
    What's the context? I mean, are you talking about case fans (not CPU or video card fans)? Is this a high performance/overclocked PC? What's the noise issue - is the fan squealing (which means a bad bearing) or just a fast/loud woosh? Fan size? (If you can swap in a larger fan, it doesn't need to work as hard.)

    Anyway, I've balanced ceiling fans, but I can't imagine trying to balance a computer fan. If it's a case fan, I'd suggest looking at Nexus fans or other fans designed for low noise. They also install with rubber case mounts so they don't transmit vibration to the case. You might also want to look at www.silentpcreview.com for ideas (that's a quiet PC site that's been around for years, and has some pretty detailed information). There's usually more to quieting a computer than just the fans anyway.

    "The problem with quotes on the Internet is that it is hard to verify their authenticity." Abraham Lincoln

    I say there is an invisible elf in my backyard. How do you prove that I am wrong?

    The Leif Ericson Cruiser

  10. #10
    Join Date
    May 2007
    Location
    New Haven, Connecticut
    Posts
    7,059
    Quote Originally Posted by tashirosgt View Post
    I'm glad you explained that. I've never dealt with ceiling fans. The ceilings in my house are too low for them.
    I have one in my kitchen. It was one that mounted closest to the ceiling that we could find. Unfortunately, one of my wife's friends is tall enough for it to be a problem on the rare times he & his wife visit.

    Not a problem for me -- I elected the "less than 6 feet tall" radio button when I was setting up my customization.
    Information about American English usage here and here. Floating point issues? Please read this before posting.

  11. #11
    Join Date
    Jun 2009
    Posts
    1,383
    To balance a computer fan, you'll have to remove it and either add weight(tape,glue, or even start cutting the blades) or you need to heat the fan up a bit and bend blades.

    Since most of them are cheap brushless fans, they don't last forever. Why waste time optimizing a garbage component? Either replace the fan with something quieter, or just clean it. If i'm building my own electronics, i tend to use such large heatsinks that i dont need a fan. For a PC, i simply clean the fans and set the bios to control fan speed based on temperature. A good bios doesn't cause problems, it's actually where the treatment is found.

    The worst fans can be the smallest ones. Like the video card and cpu.

  12. #12
    Join Date
    Jul 2011
    Posts
    496
    Quote Originally Posted by ShinAce View Post
    I learned a few things about fans when i was building amplifiers. The first is that you really don't need a lot of air, just a slight breeze. Look at the fan on a laptop or playstation3. Tiny! The second thing i learned is that a 12 volt fan will spin up with 5 volts.

    I used to take a 12 volt fan that was bigger than i needed and use a resistor to give the fan 6 volts. I now have leftover 50 ohm 5 watt resistors for the future.
    My approach was similar. I purchased a nice tower case with rock-solid power supply for my workstation project. Although it has space for four fans, it only came with two, mounted in the front, and they were very loud. They pull air from the case. I rewired them in series, and added two more fans in the back wired the same way, but pushing air into the case. According to the onboard proc thermometer, it runs about 2 deg C cooler, although with about half the noise.

    The power supply fan is still very noisy. There's a means of adjusting the fan for the power supply through the BIOS, but I'm hesitant to fiddle with it because I'm running two power-hungry video cards. I've thought about disabling that altogether and orienting all fans to ventilate outward. I'm sure that would create enough flow through the power supply to keep it cool, but there might be dead spots inside the case if that happens -- at least one of the rear fans has a duct that blows directly onto the processor.

    Oh, the joys of trying to figure out how to ventilate your computer case! Perhaps I should drill a couple of small holes through the side in strategic locations and simply insert a meat thermometer!

Similar Threads

  1. Balancing Eggs
    By jsuttile in forum Astronomy
    Replies: 3
    Last Post: 2007-Mar-14, 12:05 PM
  2. The latest on egg balancing
    By jdmack in forum Science and Technology
    Replies: 6
    Last Post: 2005-Dec-18, 12:41 PM
  3. Egg Balancing
    By Issflareman in forum Phil Plait's Bad Astronomy
    Replies: 45
    Last Post: 2005-Oct-11, 02:34 AM
  4. balancing equations
    By metal_dragon35 in forum Astronomy
    Replies: 13
    Last Post: 2004-Dec-15, 02:29 PM
  5. Apollo Guidance Computer and Other Computer History
    By jrkeller in forum Conspiracy Theories
    Replies: 0
    Last Post: 2004-Mar-29, 03:07 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
here
The forum is sponsored in-part by: