Ducting Material Advice

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gb115b
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Ducting Material Advice

Post by gb115b » Tue Oct 02, 2007 1:58 pm

hi i was wonderign what people advised for ducting material...

any advice on what to get, and where to get it (i'm in the UK)

Bluefront
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Post by Bluefront » Tue Oct 02, 2007 2:10 pm

You can make ducts out of many different materials.......but the easiest material to use is a flat sheet of thin aluminum. You can buy the stuff at hardware stores in rolls, or in smaller flat squares used for roof flashing.

The advantage here.....it is easy to cut, and it will hold any shape when bent. Cover it with a piece of sticky-back felt from a craft store to prevent shorting out. Here's a four-piece duct, held together with velcro.

Image

cmthomson
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Post by cmthomson » Tue Oct 02, 2007 2:17 pm

Opinions vary. I like to use Styrene for ducts once I've finalized on their shape: it's stiff, non-conductive, and easy to cut and glue (but doesn't bend well at all).

By far the easiest is cardboard, either corrugated or cereal-box, taped together.

autoboy
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Post by autoboy » Tue Oct 02, 2007 2:53 pm

Cereal box is my prefered material. Thin, easy to work with, and totally free, unless you don't like cereal. Use the brown side if you don't want Captain Crunch peering out at you when you open the case.

Felger Carbon
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Post by Felger Carbon » Tue Oct 02, 2007 3:25 pm

autoboy wrote:Cereal box is my prefered material. Thin, easy to work with, and totally free, unless you don't like cereal. Use the brown side if you don't want Captain Crunch peering out at you when you open the case.
Double-sided tape makes it easy to anchor the cardboard to the fan casing on one end and the Ninja fins on the other.

Captain Crunch works; but for a classy job Ritz cracker boxes are best. :D

Plan and cut your pieces carefully:

Image

The green stuff is the "stickem insulation" that allows the double-sided tape to come in a roll!

Image

I got 7C better cooling with this two-piece duct than with no duct. OK, so I put some double-sided tape on the wrong side of the first piece I taped...

Image

edit: added pics

gb115b
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Post by gb115b » Wed Oct 03, 2007 7:43 am

brilliant! thanks for all your advice!

...i think i'll hunt around for some styrene...as i'm planning on putting acoustic insulation on it, and i think the sturdyness would come in handy (as i'm planning making a large duct for my PSU

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Post by nutball » Wed Oct 03, 2007 8:20 am

I use foam-board, which you can get from office supply stores, eg. Staples. It's rigid and cuts easily.

ronrem
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Post by ronrem » Thu Oct 04, 2007 1:22 am

Sometimes a container like a juice bottle or milk jug or other recyclable plastic food/juice/booze container also can work.

The foam board idea ain't bad....looks less ghetto than the Ritz box.

It might be cool to go for the ghetto look,use a Kotex box and seal 'er up with some tacky lookin' christmas tape :lol:

You could even get creative and use a plastic toy..a doll's head...something weird. clear plastic/acrylic would look classy 8)

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Post by Felger Carbon » Thu Oct 04, 2007 9:32 am

ronrem wrote:...looks less ghetto than the Ritz box.
You clearly don't understand that Ritz cardboard is ritzy! :D

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Post by Bluefront » Thu Oct 04, 2007 9:51 am

I am truly surprised by some of these suggestions. Regarding cardboard and other hard materials......noisy. Take the cardboard tube from a roll of paper towels.....now talk or make some noise through one end. The sound is amplified, like a little speaker.

Now make a tube out of something with a soft lining........ like the aluminum with a felt covering like I suggested. Sounds through it are muted, compared to a hard-sided tube.

Remember this is SPCR.....not NoiseAmplificationReview. :lol:

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Post by EndoSteel » Fri Oct 05, 2007 7:44 am

Bluefront
The sound is amplified, like a little speaker.
If there is sound. A 600 RPM fan doesn't make any.

Now make a tube out of something with a soft lining........ like the aluminum with a felt covering like I suggested. Sounds through it are muted, compared to a hard-sided tube.
But flow impedance increases considerably, especially if the duct is curved.

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Post by Felger Carbon » Fri Oct 05, 2007 8:25 am

I'm always on the lookout for new construction materials that I can buy online (not much selection in my barely-civilized location). Now, I've never used foam-board or styrene, but here's what I found on-line:

Staples carries foam-board, but it's 3/16" thick - nearly 0.2" or 5mm. Search "foam-board" at staples.com.

Styrene? An embarrasment of riches. One on-line store, only one brand, yields 7" by 12" white styrene sheets of thickness .01", .02", .03", .04", .06", .08", .10", .125". $3.59 gets you 4 sheets of .04 (LXDL94) or 7 sheets of .02" (LXDL92). See here.

You will apparently need polystyrene model cement. Dunno a brand and/or model number. Perhaps CM Thompson can provide some pointers? Or you can use the search or advanced search at Tower.

Evergreen is another company that sells sheet styrene at Tower. Also, you can buy styrene rods, I-beams, L-angles, U-channels, and box beams. This stuff is made for serious model construction. Many many variations. Not particularly costly as hobbies go. I would never have believed that one store could carry so many different parts made of styrene! :D

edit: corrected typo in "LXDL94"

ronrem
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Post by ronrem » Tue Oct 09, 2007 1:35 am

Felger Carbon wrote:
ronrem wrote:...looks less ghetto than the Ritz box.
You clearly don't understand that Ritz cardboard is ritzy! :D
Ritzy..or Cheesy? It's a matter of taste :roll: If it tastes cheesy...it's cheesy. :lol:

mellon
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Post by mellon » Tue Oct 09, 2007 4:24 am

Clear plastic desk cover (meant for protecting a desk when writing on top of it) worked for me. Available at office supply stores and easy to cut & bend & tape. Here's my GPU duct using the stuff: viewtopic.php?t=43858&highlight=

gb115b
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Post by gb115b » Tue Oct 09, 2007 4:54 am

http://www.modellersmate.co.uk/products.htm

i saw this for the uk which stocks evergreen sheets...

i think this is what i'm going to go for...will put pics up of my rig, once i'm ready...

Felger Carbon
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Post by Felger Carbon » Tue Oct 09, 2007 9:02 am

gb115b wrote:i saw this for the uk which stocks evergreen sheets...
I see they stock both Plastruct(sp?) and Evergreen, which seem to be the two biggies re styrene modelling products.

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Post by Fayd » Wed Oct 10, 2007 7:14 pm

i have the fans in my computer held in place with duct-tape :/

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Post by cmthomson » Thu Oct 11, 2007 3:31 pm

The "glue" used for styrene is a solvent with a thickener added. It temporarily softens the styrene, then forms a strong bond, just the way PVC cement works with piping.

The "glue" I use is actually acrylic cement.


Styrene is the preferred material for most model railroad construction. In addition to being sturdy, easy to cut and easy to glue, it takes paint well. If there is a model railroad club or shop in your area, they will be delighted to expound the virtues of styrene...

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Post by BugFix » Tue Nov 06, 2007 4:42 pm

You can make ducts out of many different materials.......but the easiest material to use is a flat sheet of thin aluminum.
You can't possibly be serious. That's an easy recipe for a dead motherboard or power supply. If that felt (which is not a particularly good insulator, especially if you have a humid environment where it might get damp) peels off a little, or you drop it prematurely, or a sharp solder bead pokes through, ZAP!
I am truly surprised by some of these suggestions. Regarding cardboard and other hard materials......noisy. Take the cardboard tube from a roll of paper towels.....now talk or make some noise through one end. The sound is amplified, like a little speaker.
That's not amplification, just reflection. The tube acts as a guide for whatever sound is coming in from the other end, nothing is getting louder (think of a car muffler, which is made entirely of sheet metal -- it's certainly not amplifying things).

And yes, some materials reflect sound better than others (although cardboard, as these things go, is a pretty good sound absorber for a rigid material). As you suggest, felt is a good choice for damping these reflections. Although I'd strongly suggest sticking it on something NON CONDUCTIVE.

For myself, I find heavy cardboard an excellent choice. Easy to cut, easy to assemble, rigid, and cheap.

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Post by Bluefront » Tue Nov 06, 2007 5:25 pm

Uh.....look. We're talking about a duct here. Even bare aluminum would be ok if the thing was mounted properly. That felt is permanent...won't fall off. The thing that makes thin aluminum attractive....it can be bent and formed by hand. And retains it's shape.

If you really worry about shorting, cover it with duct tape, then felt.

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Post by VanWaGuy » Tue Nov 06, 2007 10:38 pm

Bluefront, I love your signature, and many of your posts, but as many times as I have said water and electronics do not mix to the water cooling crowd, I certainly would be even more alarmed recommending a conductive material such as aluminum in the hands of amateurs.

Properly shaped, and mounted securely, it might make a great duct, but if it comes lose, slips, etc, that would be :evil: .

Bluefront
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Post by Bluefront » Wed Nov 07, 2007 3:01 am

Well that may be.....but IMO, anybody far enough into computer mods who is attempting to construct a duct of some sort, is no longer an amateur. Some people have entire cases made from bare aluminum, brackets, mount cages, etc. I'd be more afraid of a screw dropping on something "hot", than a felt covered piece of sheet aluminum. :lol:

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Post by Steve_Y » Thu Nov 08, 2007 3:59 pm

Regarding noise amplification due to thin cardboard ducts; I've used cereal box ducts in a few PCs, and for the most part I haven't found that they've increased noise.

The one exception was when a duct was vibrating against the side of the case, adding a buzz that was much louder than the fan it contained. A couple of layers of duct tape reinforcing the cardboard and holding it in place removed the noise problem completely.

Cardboard's rather ghetto, but it's also extremely quick and simple, uses materials that are free and easily available, and in my experience works fine. A few minutes with a pair of scissors and some tape and you've got a duct. If it doesn't fit properly then you can just snip off a bit more cardboard. If you make a total mess of it then you just have to get another box to cut up. For such a simple and low cost tweak I've found it makes a pretty big difference to system temperatures.

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Post by gb115b » Mon Nov 12, 2007 3:57 pm

i'm going with styrene sheets with acoustipack on the inside...

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Post by ultrachrome » Mon Nov 12, 2007 4:27 pm

If the fan (noisemaker) is at the end of the duct at the back of the case, why bother with sound absorption inside the duct? What noise is it absorbing?

I picked up some pva foam from a hobby shop. Lightweight, flexible, and easy to cut. I tack it together with crazy glue. The glue soaks into the foam so that square joints stay square.

Image

gb115b
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Post by gb115b » Tue Nov 13, 2007 5:04 am

my duct is to feed fresh air to my PSU from the front of my case...it needs to be sturdy enough to mount a fan at the intake end...

the acoustipack is going to be used as
a) i have some lying around
b) to add soem weight to it, hopefully lessening vibrations...

c) it'll hopefully cover up what a mess i make of my duct too!

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