Nice box, looks like it should be real quiet as well. Have you thought aabout maybe putting some sound absorbent material on the intake & exhaust baffles to further reduce the fan noise? I've heard good things about rebond carpet foam...

Gooserider

LOL...TRIPPLE post!



I have already asked an accoustical engineer what to use. He said to use Owens Corning Fiberglass Board #703 Here is the Owens Corning product page for it: http://www.owenscorning.com/comminsu...ct=1&System-83 The thinnest that stuff comes is 1" (up to as thick as 4"). The accoustical engineer said the thicker the better as the thin stuff doesnt absorb the low frequencies very well. However I haven't been able to find this stuff anywhere. I even called Owens Corning directly (1-800-GET-PINK) and asked for dealers which sell their product. All they could recommend was Home Depot bascially. I went to Home Depot and asked but the guy I talked to their didnt have any idea what I was talking about.


The engineer also recommended using Mason NDA Mounts to isolate the pump. Here is the product page for these things: http://www.mason-ind.com/about_neopr...unts.htm#specs I know of a place that sells these but I have not got around to getting any yet.

Yeah, either the site or my browser was acting up last night, kept giving me 'unable to connect' messages, and I'd keep hitting the post reply button each time (I generally use the quick reply box) and eventually it would go through. I guess it was getting in some times but not posting back to me.

In terms of the box, your engineer friend is probably right from a theoretical standpoint, the products suggested are very good. (BTW, have you checked w/ McMaster Carr for them?) but may not be practical from either a cost standpoint or just that us mere mortals can't find anyplace to purchase them.

I also spend a lot of time over at Silent PC Review (SPCR.com) where there is a great deal of interest in this sort of material, and a great deal of experimenting with 'poor man' solutions using more readily available material. Personally I've found aluminum faced asphalt roofers tape is great for killing case resonance (Probably not an issue with your box) and have seen lots of good reports on the use of rebond foam carpet padding as a sound absorber in cases where space is limited. The combo is said to compare well to Acoustipak at a fraction of the cost. In the case of your box (which I think many over on SPCR would love BTW) I would probably go with 1" thick egg crate foam tiles (available for ~ $1.oo each on E-bay) for the baffle lining, and sorbothane rubber (from McMaster Carr) for the pump isolation.

Gooserider

I'm thinkin of h2o cooling the Bottom of the HDD. Those chips that are @ the PCB are often hot or is it the source of heat even if the RPM is an issue.
Any comments?

If your gonna WC a HD you need to cool the sides as they are designed to output the heat from the side panels.

Buzz

True.


However, there is always a different way of doing things :)

I chose to make a large flat water block that covered the bottom of my 3 HDs (2 of which are Raptors). The drives still get quite hot this way. But thats OK because I installed two 80mm fans in the box to circulate air. I also cut up a heatsink and epoxied the pieces onto the block. That way the air gets cooled inside the box (where my pump, HD, etc are located). Refer to the pics before for a better idea of what I am talking about.

Not trying to start an arguement here or anything. Just describing the way I did it.


EDIT: Here is a pic of the HD block with the heatsinks on it. Again, the reason they are there is to cool the air in the box (since its a practically a sealed chamber where the HDs are)

With these heatsinks and two 80mm fans circulating air the temp inside the box never gets above 29'C and the HDs are cool to the touch.

http://www3.telus.net/foofoo/new_box..._heatsinks.jpg

I had this idea because I normally see fans for HDDs are installed on the bottom, w/c seems to give enough cooling.
And installing a slim block on the bottom could make it possible for small size PC Case w/ loaded Optical Drives, & HDDs. Maybe someone would to give it a try? ;)

I have NEVER seen a pointer to a drive manufacturer stating that cooling was intended to be via the drive sides. My own experience examining the sides of drives suggests that cooling that way isn't a major design factor since they seem to be designing to minimize contact between the drive and other hardware. (I.e. milling out the sides of the casting except where the screw holes are)

In some of the discussion of drive cooling that I've seen on Storage Review and other such places, the implication is that cooling ANY part of the drive will rapidly cool the entire drive both from conduction through the Al drive body, and by convection of the air inside the drive itself - note that the biggest source of heat in a drive is the air friction and turbulence caused by the platters spinning inside the drive.

Air cooling is often applied to the top of the drives simply because it is the biggest single area available. Water cooling I've seen done by applying the cooling to ANY part of the drive. The only caution seems to be that one should avoid stressing the drive casting by fastening things to it in ways the manufacturer didn't design.

Gooserider

Makes sense...what would happen to a hd sealed in a vacuum sealed box? would it remove the heat source?(air/turbulance) I'm not sure, can there be turbulance in a vacuum? I would guess not, remembering the science museum field trip where they drop a feather in a vacuum and it drops like a rock...hey don't crack on me I had to reach back to the early 80's to remember that.

I wonder if this scenerio would work: I make an acrylic box, vacuum pump out the air using something like one of those food vacuum systems via a flapper seal(no idea the technical name for it, where there is a hole covered by a piece of rubber and the vacuum in the box holds the rubber flap in place. ) be interesting to see the temp differences...and where on a hd would I place the tc sensor?

-MC

MC thats an interesting idea but i dont think it would work. I'm pretty The platter scetion of the hard drive is air tight to stop dust getting in there and messing it all up. Becuase the vacum would stop the heat being transfered through the air it may even cause the hard drive to hehat up more as the heat has no where to go.

Also builded up a vacum container that still had all the cables going throught it would be really hard.

Just my 2 pence. just stick a bit of coper on each side and WC it

Buzz

Hard drives are not sealed air tight. I know - I have taken enough dead ones apart to be sure of it.

There is always a breather hole somewhere with a filter of some kind.

Also, I remember reading somewhere that the air inside is required as it acts as a cushon for the read/write arms. At high RPMs the spinning air helps keep the heads from impacting on the disk surface.

My $0.02 on the subject...

http://www.pcguide.com/ref/hdd/op/packAir-c.html

"As discussed in the section describing hard disk head flying height, the old myth about hard disk heads and platters being "in a sealed vacuum" or whatnot, is wrong in two ways: there's no vacuum in there, and the drive itself isn't sealed, at least not in the way most people believe. In fact, air is an essential component for proper drive operation. Regular hard disks aren't totally sealed from the outside air, but they definitely are separated from it, in order to ensure that the dirt and dust of the outside air is kept away from the delicate platters and heads of the drive."

Cptn Foo Foo is 100% correct. I've had a chance to read up on this too, and I've taken a few HDDs apart myself (just don't ask why, ok? :D )

Capt Foo is on the right track - a normal civilian grade hard drive is NOT sealed (there are some special sealed military / aerospace drives, but those aren't something most of us will ever encounter) It will have a small vent somewhere on the drive housing - most drives the vent is under the drive board and not visible, but some IBM drives have it on the lid, with a big arrow pointing at it saying "DON'T BLOCK THIS HOLE" The vent leads to a HEPA type air filter and is mostly for air pressure equalisation, it doesn't actually get much circulation, however air will go in and out with pressure changes and / or as the air in the drive expands and contracts due to temp changes.

The air is a VITAL part of the drive mechanism, the drive would fail catastropically with out it. The spinning platters move the air around in the drive, this creates an airfoil lift effect on the hard drive head and lifts it off the disk surface. The lift allows the head to maintain just the right distance above the drive surface for it to read and write properly.

So no MC, putting your drive in a vaccum box would not work - it would get rid of the turbulence and heat all right, but only because it destroyed the drive!

Gooserider