Fanhole molding as fan "isolation"

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chylld
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Fanhole molding as fan "isolation"

Post by chylld » Thu Jan 01, 2004 12:27 am

Will this work? The fan would still be attached to the case with fan screws, but the fan body would be held off the case by the fanhole molding.

More specifically, I'm thinking of mounting an evercool aluminium at the back inside of my bqe. My case is already acoustically damped so I don't think vibrations would be much of a problem at all?

Zyzzyx
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Post by Zyzzyx » Thu Jan 01, 2004 12:57 am

Don't see it helping much if you still have the hard contact points of the mounting screws.

Ralf Hutter
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Post by Ralf Hutter » Thu Jan 01, 2004 6:16 am

Zyzzyx wrote:Don't see it helping much if you still have the hard contact points of the mounting screws.
I agree. You still be transmitting extra vibrations from the fans to the case that you'd be relying on the dampening material to deal with. And how succesfully it would dampen those vibrations is an unknown. Why not eliminate them in the first place and not have to rely on the dampening material to do it? The dampening material does do a nice job of reducing vibrations but it's by no means a miracle cure.

chylld
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Post by chylld » Thu Jan 01, 2004 6:22 am

That's true. I just can't figure out a reasonable way to decouple the fans otherwise. The EAR grommets apparently don't work with these fans, and those long stick ones are nowhere to be found here in Aus.

:cry:

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Post by Ralf Hutter » Thu Jan 01, 2004 7:18 am

chylld wrote:That's true. I just can't figure out a reasonable way to decouple the fans otherwise. The EAR grommets apparently don't work with these fans, and those long stick ones are nowhere to be found here in Aus.

:cry:
Directron here in the US carries the stick isolators and they ship internationally although their terms seem ever so slightly draconian.

Another possibility might be to use the Antec "Noise Killer" kits. These have the rubber gasket for the fan as well as a set of rubber washers so the fan mount screws don't bear directly on the case. This may be easier to find down there. They're also sold under the Vantec brand name for about 1/2 the Antec price, maybe you could find that down there as well.

chylld
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Post by chylld » Thu Jan 01, 2004 1:52 pm

I don't understand how they'd work any better though - the screws are still in hard contact with the case and the fan.

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Post by Ralf Hutter » Fri Jan 02, 2004 4:40 am

chylld wrote:I don't understand how they'd work any better though - the screws are still in hard contact with the case and the fan.
No, the screws aren't in hard contact with the case. There is a rubber washer between the head of the screw and the case wall.

So you've got:

1) Screw and fan in contact

-but-

2) Fan is isolated from case,

3) Screw is isolated from case.

mahkum2
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Post by mahkum2 » Fri Jan 02, 2004 11:25 am

No, the screws aren't in hard contact with the case. There is a rubber washer between the head of the screw and the case wall.
That is what I thought until I came across this image on the Vantec USA website. Does anyone here have any explanation for this warning not to use the gasket and the washer at the same time?

Image

Image

Image

chylld
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Post by chylld » Fri Jan 02, 2004 1:35 pm

Ralf Hutter wrote:No, the screws aren't in hard contact with the case. There is a rubber washer between the head of the screw and the case wall.
I suppose that could be sufficient. I just thought it was a total decoupling of the fan, but it isn't since the thread of the screw is in hard contact with both case and fan.

Gooserider
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Post by Gooserider » Sun Jan 04, 2004 10:24 pm

Why not just make your own rubber washer, and ream the holes out large enoungh that the screws don't touch the case metal. That should give isolated mounting. If the fan hole molding doesn't give enough isolation, try putting down a few layers of foam rubber weather stripping around the frame of the fan?

Gooserider

bobdoe
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Post by bobdoe » Tue Jan 06, 2004 2:19 pm

What kind of fan noise should isolation get rid of? Rattling or clicking?

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Post by MikeC » Tue Jan 06, 2004 4:45 pm

bobdoe wrote:What kind of fan noise should isolation get rid of? Rattling or clicking?
It doesn't change fan noise, per se, but the noise caused by the case panels vibrating in sympathy with the fan. If the fan is quiet and spinning slowly, the improvement is subtle to nil -- assuming a good case. With aluminum and thin paneled steel cases, the difference can be dramatic even with slow quiet fans. A kind of "hummy haze" disappears, and all the normal fan noises -- the clicking, for example --- get more muted, less sharp. It's sort of like noise in a reverberant hard room versus the same noise in a plush carpeted room.

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