custom heatsinked enclosure

[jdub765]

I was browsing ebay for solutions for quieting down my harddrives and I found this auction: http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 7504103650

The guy states that "any shape extrusion dies made."

so I was thinking, if the heatsink he already has had two fins on the edge facing down, two of them could interlock, and make an enclosure that only needs to be sealed on the ends.

I drew a pic of one heatsink


These are two heatsinks interlocked. (one is upside down)


The blue is supposed to be heat conductive pads that you buy elsewhere. I guess you wouldn't really need them though.

the pics aren't drawn to scale. But you can get an idea of what I'm talking about. All that would need to be done is to seal the ends with some foam, and maybe suspend the entire thing.

Well, I was wondering if anyone would be interested in a groupbuy or something, to cover this guy's cost for making the die for the heatsink. I'm not saying that it's going to happen for sure, as we would have to talk to him first and see what he can do, but if it does, it'd hopefully be affordable, effective, and silent solution. He sells the heatsinks by length, so all you would need is 7-7.5" pieces to enclose two hard drives.

I already emailed the guy about it to see what kind of stuff he does. If you'd be interested, lemme hear your thoughts

[jdub765]

ok, the guy got back to me and it seems that the costs are quite prohibitive...

hello
about 2000$ approximately for thismaybe 1950$ then you would have to buy 1500 lbs minimum , of aluminum to avoid the companys setup fees to make the run,@1.62$ per pound,
so there is quite a startup cost,i had to have a partner to get my first die made.
we extrude over 2 million pounds per month at extruded aluminum corporation ,where i work we are located in belding michigan,im a millwright there .i know its expensive ,i wish it wasnt,
thanks for your interest,let me know if you still want to proceed
thanks
russ

I'm not sure if that's $2000, plus a possible startup fee, but even if it isn't, 1500 lbs... each person would use about 5 lbs of alum for the two pieces, so that's 300 people. That's $8.10 a person, but it's still 300 people...

Well, I guess that's the end of this thread

[shigaloo]

the price sounds OK, what i got out of it was:

$2k for the custom die (used to make the extrusion)

then in order to avoid a fee you need to get 1500lbs minimum

but the cost is $1.62/lb

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your design does not place the fins in an optimal orientation for passive cooling and would probably still need a fan

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you might want to try something like this



it assumes you use 2 pieces of raw material in the auction

only problem is 5 3/8" depth will not allow you to fully enclose the drives without another custom piece

he might be willing to do the millwork for you if you dont have tools

[IsaacKuo]

Aluminum extrusions can be full tubes--you don't need two pieces. You still need two endcaps for a full enclosure, of course.

[IsaacKuo]

Personally, I don't see the use for either of the above designs, regardless. Any sort of hard mounting means direct transfer of noise, turning the "enclosure" into a sounding board. The second design is just ridiculous anyway, because any PC where sound is a consideration isn't going to have such a huge bank of multiple hard drives.

If you're going to do an enclosure at all, I think you ought to suspend the drive within the enclosure with a soft mounting. IMHO, the appropriate die cross section should be a rectangular tube, with four sets of heat transfer fins (both sides of the top and bottom).

[shigaloo]

Aluminum extrusions can be full tubes--you don't need two pieces. You still need two endcaps for a full enclosure, of course.

correct, but from a usability standpoint would you really want to try stuffing drives a rigid tube/box

[IsaacKuo]

Aluminum extrusions can be full tubes--you don't need two pieces. You still need two endcaps for a full enclosure, of course.

correct, but from a usability standpoint would you really want to try stuffing drives a rigid tube/box

Why not? In the interests of noise reduction, the hard drive shouldn't be touching the aluminum tube at all. The suspension system could be integrated with the endcaps, or it could be something as simple as some sticks of rubber/foam along the internal fins.

[ilh]

What's the point of heatsinks if the drive doesn't touch them?

[IsaacKuo]

What's the point of heatsinks if the drive doesn't touch them?

The same point as heatsinks anywhere else--to improve heat transfer. In this case, the internal fins improve heat transfer from the internal air to the enclosure. The external fins improve heat transfer from the enclosure to the external air.

In contrast, a typical DIY enclosure just has flat sides, so heat transfer isn't as good.

[jdub765]

Well, the way I was thinking of mounting it would have the blue heat conductive pads to help isolate the vibrations a little, and then you could use neoprene or rubber washers on the screwheads. I was thinking of having the fins horizontally so taht you could place the hard drives on the bottom of the case right behind a intake fan hole (w/o the fan), sitting on some foam. That way, if you have an exhaust fan in the back of the case, it would draw the air from the front hole, sucking in cooler air over the hard drives and heatsinks. I cut a hole in the front of my case so that air would be drawn in over the hard drives and my hard drive temps went from 55C to 33C, so it should be enough to cool the heatsinked hard drives.

[frankgehry]

You're doing this backwards. You should design and test the suspension or box or whatever it is to make sure it works, and then have someone build it. You can buy aluminum boxes and heatsinks off the shelf from an electronics supply store. - FG

[IsaacKuo]

No kidding! I've had a lot of ideas which I thought could work but when put into practice it didn't work nearly as well as I had hoped.

[jdub765]

There's not really much to test though. It's basically the sandwiching method but with heatsinked aluminum.