mounting fans

c00z · Post by **c00z** » Wed Apr 20, 2005 10:51 am

I have a quick question that I am sure you guys know alot about. I am going to redo a bunch of my fans. I want to remount them, currently I have them all mounted with rubber gromets. However, during a tour of the gallery section I have seen quite a lot of different methods. Now I am wondering what is the best method for mounting the fans. The one that interests me is the cheap and looks good method of zip ties with a huge bunch of foam for insulation. Or should I just stick with the rubber gromets?

Why I am at it, I have one more question, I am going to be modding my psu from a 80mm fan to a 120mm fan. Now is it is good idea to use foam inbetween the psu and the case to dampen any vibrations and if so where and what types of foam are preferable that done degrade, etc

c00z · Post by **c00z** » Thu Apr 21, 2005 5:20 am

Tibors · Post by **Tibors** » Thu Apr 21, 2005 6:33 am

If you have a non/hardly vibrating fan, then the mounting method doesn't really matter for noise. Ease of use becomes the most important aspect to me then and I think the rubber sticks are easier to use than the zip-tie method.

If you have a fan that does vibrate though, I have found that the rubber sticks I have don't really help much. I bought some tesa self adhesive foam weather stripping in the local DIY market. According to the text on the packaging, it is guaranteed not to degrade for at least eight years. It is availlable in several shapes. V-, E-, D- and d-profiles exist. Combine the d-profile with the zip-tie method and you should have sufficient vibration damping. Just make sure you don't tighten the zip-ties to much.

c00z · Post by **c00z** » Thu Apr 21, 2005 6:51 am

Am I wrong to assume that all fans would vibrate slightly? I have found that the rubber gromets are better than screws and thus was under the impression that the zip ties with the foam would be an even greater improvement

suggestions?

Tibors · Post by **Tibors** » Thu Apr 21, 2005 7:33 am

Of course, if you would make a ranking of the different methods, then you will probably get something like this (worst to best):

tight screws
silicone gasket
rubber sticks/gromets
zip-tie & foam
foam only (See the wooden PSU testing rig for an example of this.)

Now if you have an aluminium case with a clearly vibrating fan, then you need the absolute best of these methods. On the other hand if you have a 1mm steel case with heavy damping material on all panels plus a fan that hardly vibrates, then you might not even hear the vibrations of a fan mounted with screws.

Hear is the crucial word in this. If you can hear the vibrations with a certain method, then try a better one. If you can't hear the vibrations, then a better method that requires more work/money is not really better (unless you want to keep yourself busy).

I can't hear your fans over the internet nor can I feel how stiff your gromets are, so I can't give you more conclusive advice. There are just to many parameters.

Edit: typo

c00z · Post by **c00z** » Thu Apr 21, 2005 9:13 am

I have yate loon 120mm medium speed fans in the sonata case. I dont think vibration is a huge problem, but since I am redoing the case if the zip ties and foam has a chance of being better might as well do it then as well. However, I have done a quick search of the forums. Is their any specific way of doing it, I have seen pics of it already done but am a tad unsure of the exact procedure of how to create the foam and zip tie mounts and as you mentioned dont make them too tight?>

c00z · Post by **c00z** » Mon Apr 25, 2005 8:31 am

bump...anyone have a link to pics so I can see how it is done so i can do it this week?

m0002a · Post by **m0002a** » Mon Apr 25, 2005 9:29 am

For a case fan, I lay down a layer of 100% silicone caulk and let it set up for about 30 minutes, and then use nylon screws and nuts to attach the fan. The silicone can be removed (peeled off) with only minimal effort if the fan needs to be replaced (it is not really like an epoxy glue or anything close).

You can get the nylon screws and nuts at any good hardware store. The caulk is usually sold as GE Silicone II or something similar. Some fan mounts (including the ones supplied by Antec) are made from silicone, but the fan mounts either allow the fan to wobble too much, or they don't keep the fan tight against the case surface, IMO.

cpemma · Post by **cpemma** » Mon Apr 25, 2005 12:33 pm

c00z wrote:...anyone have a link to pics so I can see how it is done so i can do it this week?

It's 2 ties per mounting hole, the second tie acts as the 'nut' on the #1 tie 'bolt'. There is a picture if you search, IIRC it also uses thin rubber washers cut from thick-wall tubing.

http://forums.silentpcreview.com/viewtopic.php?t=11115

The caulk method - I once used some silicone rubber DIY auto gasket stuff, one advantage was it comes in a smaller tube like toothpaste & doesn't need a caulking gun.

m0002a · Post by **m0002a** » Mon Apr 25, 2005 1:04 pm

cpemma wrote:The caulk method - I once used some silicone rubber auto gasket stuff, only advantage was it comes in a smaller tube like toothpaste & doesn't need a caulking gun.

Yes, it comes in several packages and colors. I bought some at Home Depot called "GE Silicone II Window and Door" that comes in a small tube like toothpaste.

c00z · Post by **c00z** » Mon Apr 25, 2005 7:32 pm

Wouldnt a foam pad of some sort be better than sealing caulking since sealng caulking isnt made to dampen as much as it is made to form seals?

Anyone with a link or a pic of some nice foamed fans...just trying to get the idea of how to go about it

m0002a · Post by **m0002a** » Mon Apr 25, 2005 7:51 pm

c00z wrote:Wouldnt a foam pad of some sort be better than sealing caulking since sealng caulking isnt made to dampen as much as it is made to form seals?

100% silicone caulk has lots of uses. The main reason that it is used as a caulk or sealant is that it remains pliable virtually forever and never dries out or cracks.

100% silicone is excellent at absorbing shocks and vibrations and for fan isolation. It is the material used for some soft fan mounting pins (such as Antec). I also used a thin layer when I mounted my PSU (where there would normally be metal to metal contact).

Back in my analog audiophile days, silicone caulk was widely used to make homemade turntable feet for optimum isolation, and to dampen the inside of the turntable.

The main reason it is called “caulk” or “sealant” is that the construction and remodeling market for those uses are significantly larger than for quieting PC’s and other similar uses.

BTW: I heard that the FDA is considering allowing one company to start making silicone breast implants again.

m0002a · Post by **m0002a** » Mon Apr 25, 2005 8:00 pm

Here are some pre-molded silicone gaskets from Antec (the Noise Killer 120):
http://www.antec.com/Search.bok?searchp ... =25&no=263
The also make premolded silicone gaskets for PSU's and other uses inside the case.

Tibors · Post by **Tibors** » Mon Apr 25, 2005 8:34 pm

If you search the forums for comments about those premolded silicone gaskets (from several brands), then you will see that most people consider them quite ineffective. That is why I listed them as the second worst method above. So unless the silicone caulk from a tube is a lot softer than the silicone in the premolded gaskets, it will get the same verdict.

m0002a · Post by **m0002a** » Mon Apr 25, 2005 8:48 pm

Tibors wrote:If you search the forums for comments about those premolded silicone gaskets (from several brands), then you will see that most people consider them quite ineffective. That is why I listed them as the second worst method above. So unless the silicone caulk from a tube is a lot softer than the silicone in the premolded gaskets, it will get the same verdict.

I suspect that the Antec gaskets are a little thinner than the amount of silicone I use, and unless you use nylon screw and nuts with rubber (or silicone) washers, then they won't do much good since the isolation is no better than the weakest link in the isolation chain.

I have used silicone, and it works very well and I have not ever heard fan vibration noise. In addition, it seals the fan to the case so that no air warm air that has just been expelled can come back in the case through the distance between the fan and the case, which sort of defeats the purpose of expelling hot air from the case.

Kimo · Post by **Kimo** » Tue Apr 26, 2005 6:15 am

I used the Zip-tie method with soft rubber grommets on my LL v1000B, and it works great.

You can use the zip-ties with closed or open corner fans, and the grommets isolate the fan from the case. I have very little detectable vibration, and they are very quiet (at 5v). I am using the CompUSA maddog fans.