Cardboard ducting - Safe?
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Cardboard ducting - Safe?
Just made a cardboard duct....was bored! Well it works and it works very well! Case fan is at 7v and temp in the warmer UK weather today is 29C whilst im using it so a bit more than idle temps. CPU is a 2.26Ghz P4 which draws 67.6W apparently.
So what i really want to know is, are cardboard ducts safe when cpu temps get high as in about 50C. Is there any chance of fire?
So what i really want to know is, are cardboard ducts safe when cpu temps get high as in about 50C. Is there any chance of fire?
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Depending on the type of duct and type of cardboard, the heat might make the cardboard "floppy" and make the duct deform. So, some duct tape to maintain its rigidity may be necessary.
(I was using tissue boxes to make a L-shaped piece for a VGA card duct, much as Bluefront and Arctic cooling had done.)
(I was using tissue boxes to make a L-shaped piece for a VGA card duct, much as Bluefront and Arctic cooling had done.)
Great! I've used ducts for over 5 years in my systems wherever practical, as they can make a massive difference to temperatures.BenW wrote:Thats what i needed to hear
Thanks, cant believe how much difference it makes!
And I've always used cardboard (from cereal packets usually! ) with no problems. You'd burn out just about every component in your PC before the cardboard caught fire! And I don't even know how you'd get it that hot without doing something stupid like pumping 500V into the PSU!
But as Ducky says secure it with some duct tape to keep it in place and to prevent it warping.
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Well I wouldn't use cardboard in any computer project.....even as a temporary test. It won't catch fire, but there are better materials to use.
I use flat pieces of soft plastic......such as a "for sale" sign from a hardware store. They are much more durable, can bend without creasing, can be "duct taped" over and over, and can form a permanent part of your setup.
Plus you might not be accused of a ghetto mod....
I use flat pieces of soft plastic......such as a "for sale" sign from a hardware store. They are much more durable, can bend without creasing, can be "duct taped" over and over, and can form a permanent part of your setup.
Plus you might not be accused of a ghetto mod....
Well as promised i just took some pics, chance to test out the camera on my lovely new K750i. All pics taken in a pitch black room with night mode and flash on phone. Macro mode ondentaku wrote:Can you show us a picture of what you've done?BenW wrote:Thats what i needed to hear
Thanks, cant believe how much difference it makes!
Overall pic:
Gap between GPU and duct. Half the northbridge heatsink is in the duct:
Gap between PSU and heatsink/duct:
Last edited by BenW on Sat Jul 02, 2005 1:01 am, edited 1 time in total.
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I've always been a little reluctant to put anything cardboard inside my case, but I've come to realise that it's a silly thing to worry about. I doubt any component inside my PC would still be functioning by the time it was hot enough to burn cardboard.
I've just chucked together a simple cereal box & sticky tape duct to direct air from a case fan (92mm Nexus @ 7v) to a passively cooled 600Mhz PIII. It was already running at a perfectly acceptable temperature (under <50C at full load on a hot day), but the duct has reduced CPU temperature by around 7-8C. It means that I could upgrade to a faster CPU (maybe even a 1Ghz PIII?) and still have acceptable temperatures. I'd be happy with that level of temperature reduction if I'd achieved it by paying for a fancy heat sink, not bad for less than 10 minutes work.
I've just chucked together a simple cereal box & sticky tape duct to direct air from a case fan (92mm Nexus @ 7v) to a passively cooled 600Mhz PIII. It was already running at a perfectly acceptable temperature (under <50C at full load on a hot day), but the duct has reduced CPU temperature by around 7-8C. It means that I could upgrade to a faster CPU (maybe even a 1Ghz PIII?) and still have acceptable temperatures. I'd be happy with that level of temperature reduction if I'd achieved it by paying for a fancy heat sink, not bad for less than 10 minutes work.
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Let me add another 2c. There are better materials to use than cardboard. Straight cardboard has a relatively stiff, hard surface......perfect for noise reflection. When I build ducts now-days, I use soft, bendable plastic materials.......but I cover all surfaces with sticky-back felt material. It has the ability to absorb some sound and quiets the airflow.
You could cover cardboard with the felt also. Felt around the edges can comform to irregular surfaces.....and seals much better than a cardboard or plastic edge.
Any flat surface in your case can reflect sound, and can be quieted with a felt or foam covering.....easy/cheap to do.
You could cover cardboard with the felt also. Felt around the edges can comform to irregular surfaces.....and seals much better than a cardboard or plastic edge.
Any flat surface in your case can reflect sound, and can be quieted with a felt or foam covering.....easy/cheap to do.
Well, its a warm day so i decided to find out just how well the duct works.
Side panel on, duct in place - idle = 32C
Side panel off, duct off - idle = 50C!!!!
Speedfan screenshot to show what happens when i put the duct/side panel back on:
I promise that high temp is idle (Just browsing the web, 2 windows open and winamp playing)
Sorry, bluefront...just read that. Whilst foam may quieten it, i dont think the pc is anywhere near quiet enough to notice a difference.
Side panel on, duct in place - idle = 32C
Side panel off, duct off - idle = 50C!!!!
Speedfan screenshot to show what happens when i put the duct/side panel back on:
I promise that high temp is idle (Just browsing the web, 2 windows open and winamp playing)
Sorry, bluefront...just read that. Whilst foam may quieten it, i dont think the pc is anywhere near quiet enough to notice a difference.
Just had a though. How about putting a curved piece of paper inside the duct, should help direct the airflow and stop it getting caught in the duct
Before
After
Before
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CPU
Rear Fan __|
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CPU
Rear Fan __/|
I don't see why you can't try it, as long as at no point in the duct the overall cross-sectional area becomes restrictive. Like if you did this (exaggerated) it'd be bad:
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| |
----------------| /|
F / |
A / |
N / |
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Hehe....you speak the truth, Isaac. I've come to regard you as the ghetto-mod guy. I have no fears of those either, since I have no pretty windows in any of my cases and would rather have something that works, than something that's pretty.IsaacKuo wrote:I never shy away from cardboard or "ghetto-mods", but I do tend to use clear plastic rather than cardboard most of the time. There's less fabrication effort since I can usually find suitable shapes to start from, it looks cooler, and it's a LOT easier to see where to punch the mounting holes.
however, the time may be coming soon when one of my PC's DOES have a window. Where do you get clear plastic from? Does it come in sheets, or are you talking the odd clear-plastic candy container cut to fit the need? I've been to the local craft store and couldn't find any clear plastic. I'd really like something clear, but with a bit of color, so ducts will be something nice to see in a windowed-PC.