Question about CableGami

Enclosures and acoustic damping to help quiet them.

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ONEshot
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Question about CableGami

Post by ONEshot » Mon Jul 12, 2004 12:59 am

Is it safe to route those IDE cabes DIRECTLY behind the motherboard?

As in, the IDE cables are touching the metal and plastic of the motherboard?

And same with power cables?

ChucuSCAD
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Post by ChucuSCAD » Mon Jul 12, 2004 5:37 am

Most of the time when people route the cables behind the motherboard they attach them to the metal of the motherboard tray. Thus there is no contact between them and the motherboard itself. However if contact were to occur as long as the cables did not have any nicks in the sheilding everything should be fine. However the underside of a mobo can be littered with sharp solder points. So if a cable where to rub just a bit the sheilding would wear away and zip zap you got something fried.

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Ralf Hutter
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Post by Ralf Hutter » Mon Jul 12, 2004 5:57 am

I've always been real careful when I run cables between the mobo and it's mounting tray. There's 50 bazillion sharp metal wires sticking out the back of a typical mobo and if any of them punctured the plastic jacket and made contat with the wire inside, things could get pretty interesting, and not in a good way. I run few wires (be it IDE cables or power cabling) behind the board and when I do, I take great care to make sure that they're laying real flat and not getting pinched by any of the wires that protrude from the mobo.

Tibors
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Post by Tibors » Mon Jul 12, 2004 6:07 am

I just put a new SLK-948U heatsink on a mobo. Between the backplate and the mobo goes a little sheet of clear flexible, but very tough plastic. If you can find a larger sheet of that, then you could put that between the mobo and the cables.

ONEshot
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Post by ONEshot » Mon Jul 12, 2004 2:51 pm

What kind of material is the backplate shield cover?

Tibors
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Post by Tibors » Mon Jul 12, 2004 3:24 pm

I don't know what it is exactly called in english, but I have plastic document holders with clear covers. Like these. (The site is in dutch, but a picture says.....). They come with different types of clear plastic front cover. Weak ones and slightly harder ones. If you try to fold the harder ones, the fold becomes milky white.
The backplate shield cover is made of that kind of plastic.

gbass01
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Post by gbass01 » Mon Jul 12, 2004 4:21 pm

Sheets of plastic may build up an electrostatic charge. Doesn't sound like a good idea.

Pgh
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Post by Pgh » Mon Jul 12, 2004 4:56 pm

Something else I've always wondered about cable-gami... how much risk is there to breaking the internal wires when making a flat fold in ribbon cables?

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Post by ChucuSCAD » Mon Jul 12, 2004 5:06 pm

Pgh wrote:Something else I've always wondered about cable-gami... how much risk is there to breaking the internal wires when making a flat fold in ribbon cables?
I wouldn't worry about that. If you were to bend the wire back and forth over the same spot a million times then you may have a problem. But if you were to bend it over once and let it be you should be just fine.

As for the Plastic Sheet idea I would have to agree with Gbass01 off the shelf acetate stores a mighty charge. The stuff that came with the heatink is probably coated, or atleast I would hope so.

If you are REALLY worried about it scraping, keep in mind there should be 5/16"(8MM) between your motherboard tray the the board itself. Now of course you should subtract 1/16(1-2mm) or so for the nubby bits sticking down. Giving you a full 1/4"(6-7mm) to work with. And if you want to be super super careful you could simply put black, well it does come in all sorts of fancy colors these days but you get the point, electrical tape on the back to smooth the bumps.

hope this helps a bit.

chucuSCAD

al bundy
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Post by al bundy » Mon Jul 12, 2004 6:26 pm

ChucuSCAD wrote:... If you are REALLY worried about it scraping... if you want to be super super careful you could simply put... electrical tape on the back to smooth the bumps...
I once saw duct tape stuck to the underside of a motherboard for that very same reason (protection of cables routed under the motherboard). I don't know if using duct tape for this is a bad idea or not, but your comment about the electrical tape reminded me of this...

8)

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Post by swivelguy2 » Mon Jul 12, 2004 6:43 pm

gbass01 wrote:Sheets of plastic may build up an electrostatic charge. Doesn't sound like a good idea.
nevertheless, it is still an insulator. Charge will only build up in a location if that spot is rubbed with something, and can only be discharged into something touching that particular spot. Furthermore, atmospheric moisture will tend to gradually neutralize any static charges on something like a plastic panel or sheet. I don't really see there being any danger of static discharge from plastic inside a computer.

al bundy
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Post by al bundy » Mon Jul 12, 2004 7:03 pm

swivelguy2 wrote:
gbass01 wrote:Sheets of plastic may build up an electrostatic charge. Doesn't sound like a good idea.
nevertheless, it is still an insulator. Charge will only build up in a location if that spot is rubbed with something, and can only be discharged into something touching that particular spot. Furthermore, atmospheric moisture will tend to gradually neutralize any static charges on something like a plastic panel or sheet. I don't really see there being any danger of static discharge from plastic inside a computer.
I have seen some of the external 2.5" harddrive enclosures using a small fixed internal sheet of plastic, to insulate the harddrive electronics from the metal case housing...

8)

Bean
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Post by Bean » Mon Jul 12, 2004 7:40 pm

one of my power supplies has a thin plastic sheet glued on its bottom surface to prevent the pcb from touching the housing - stock not modded.

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Post by ChucuSCAD » Mon Jul 12, 2004 8:14 pm

swivelguy2 wrote:
gbass01 wrote:Sheets of plastic may build up an electrostatic charge. Doesn't sound like a good idea.
nevertheless, it is still an insulator. Charge will only build up in a location if that spot is rubbed with something, and can only be discharged into something touching that particular spot. Furthermore, atmospheric moisture will tend to gradually neutralize any static charges on something like a plastic panel or sheet. I don't really see there being any danger of static discharge from plastic inside a computer.

I would beg to differ. Your computer is not stationary. There will always be small vibrations generated by the computer and a charge will be built up and it will discharge at some point.

As for the atmospheric moisture reducing built up static charge. I lived in GA for many many many years with 70-100% humidity and I got static zapped just as often as I do out here in Arizona with 0-0% humidity. If there is a scientific principle at work here I don't understand it.

As for the PS and HD that have been mentioned that come with a protective plastic bit, they have been specially coated.

To compare to something more obvious. You wouldn't dare put a stick of ram in a Ziplock brand bag would you? But you don't seem to have a problem putting it in one of those coated pink zip bags, or one of the newer clear ones(I don't like to use them because I am parinoid but they look the same as a standard ziplock just heavier). They are both plastic. One has just been treated.

I personally wouldn't be worried about contact between the cables and the motherboard. If you are building up enough wires/cables to fill in a 1/4" of space you may want to route things another way. I have found you can hide a multitude fan and power cables tight against the roof of the case near the edge. This usually requires the lengthening of power cables, but this is simply done with a trip to the hardware store for some wire, solder, and electrical tape.

As for the comment made about Duct tape. It would probably not hurt anything as long as you didn't want to take it off. Duct tape tends to leave nasty residue when pulled off. I however havn't messed with it and would stick to the electrical tape.


chucuSCAD

CRT_Leech
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Post by CRT_Leech » Tue Jul 13, 2004 8:34 am

Just use the plastic bag that your motheroard came in (which better be an anti-static bag!).

You could cut it or fold it to the appropriate shape/size, or otherwise punch holes in the appropriate locations, with the opening facing the side where your cables will entering/exiting and you should be good.

Even better, place them behind the motherboard tray, if your case allows it.

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Post by dasman » Wed Jul 14, 2004 9:11 am

I ran 4 IDE cables from a RAID card under the mobo without a problem (see here) -- I taped the cables down with packing tape in 3 spots too keep the cables flat.

Dave

ONEshot
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Post by ONEshot » Wed Jul 14, 2004 6:19 pm

Hrm... So what kinds of tape are safe underneath the motherboard.

And about putting wires under the motherboard, my plan is to sort of outline the motherboard's perimiter directly on to the case, and then put the wires there before hand. It seems to me that that's the only way to get it UNDER the mobo. Am I right? Or how did you guys do it?

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Post by josephclemente » Wed Jul 14, 2004 10:09 pm

I am running my wires behind the removable motherboard tray. I used a nibbler and made some small holes to neatly route the SATA cable and other wires.

I can remove my cables without any need to remove the motherboard.

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Post by Tibors » Thu Jul 15, 2004 5:12 am

CRT_Leech wrote:Just use the plastic bag that your motheroard came in (which better be an anti-static bag!)
There is another thread on this forums, where someone fried a mobo by placing it on that bag. Those bags are made anti-static by applying a conductive layer on the outside.

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Post by CRT_Leech » Thu Jul 15, 2004 9:53 am

Tibors wrote:
CRT_Leech wrote:Just use the plastic bag that your motheroard came in (which better be an anti-static bag!)
There is another thread on this forums, where someone fried a mobo by placing it on that bag. Those bags are made anti-static by applying a conductive layer on the outside.
Doh!

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