Help shortening PSU cables

[c.ruel]

Basically I have a microATX case and a non modular psu and the cables are everywhere. No amount of cable ties are going to solve the problem, the cables just need to be shorter! I have had a little bit of a search on google and seen some guides showing you how you can deattach the interface/connector on cables, shorten the cable and then re-attach the interface or, alternatively guides showing how you can just cut a middle section out of a cable and just crimp the end attached to the psu and the end with the interface on it back together and then wrap some thermal tape or something around it. Obviously the second method is much less neat asthetically but i am thinking if I just put some sleeving round it, it should look fine.

Just want to know which method is easiest safest and cheapest and what tools I should get to do it properly.

I am tempted by the crimping method (crimping is just clamping two wires together and then wrapping something round them to secure them right!?) because it seems the simplest and also the cheapest as I could just get a tool like this one right and I wouldn't need a soldering iron on anything like that, which some guides say you need to do it the other way!?

Also I am a bit worried about messing up the cables by doing this so I am thinking of just doing this with the PCI-e cables, 4 pin molexs cables and Sata cables. Think I might leave the 20+4 pin alone and the 8-pin cpu cable. If i just do those cables will the risk be alot lower.

Thanks in advance.

[peterb]

Depends how handy you are with a soldering iron. Certainly the simplest method is to cut out the section of cable between the PSU and the connector, slide some heat shrink (or other sleeving) over one of the ends, solder the joint (overlapping joint) and then slide the sleeving/heatshrink over the joint (and in the case of heat shrink - shrink it) You could put braid on the cables at the same time (which would disguise the work, but in that case you would need to make one cut near the end of the cable (PSU or connector) so the job would be a bit more fiddly.

The other option is to open the PSU, unsolder the cables from the PSU cct board, shorten the cable (and add braid if required) and then resolder the shortened connectors.

You should only do that if you are happy working on mains powered equipment, and have the knowledge and skill set to operate safely on circuits with high energy storage components. (Discharging capacitors before starting work, considering the use of shorting caps to avoid relaxation effects, and confident in your skill of hand in making good quality soldered joints.)

If you cannot answer yes to the last paragraph DO NOT ATTEMPT IT!

The other option - removing the connector is one I would avoid. It is very difficult to undo and remake a crimp connector - they are designed for speed and ease of assembly and intended to be permanent. If you can get the crimp connectors to go into the shell, and you can get the proper crimp tool, then it is possible, but I think the cost would be prohibitive for a 'one off'. It is possible to crimp connectors using pliers, but the qhaulity of the joint is dubious, and if it is a connector carrying several amps, you don't want to compromise the crimp at all - a high resistance joint (relativey high) will degrade the regulatuion of the supply, and lead to overheating of the joint causing damage to the shell and in extreme cases, the risk of fire.

But again it comes down to your particular skill of hand.

The crimp tool you linked to is designed to crimp RJ45 connectors - and would not be suitable for any other application. You could use the standard bullet type connectors, or cable joints, but I suspect that the size of the joints would make the cable harness just as unweildy as it is now.

http://www.maplin.co.uk/Module.aspx?ModuleNo=44094

is the sort of thing I mean - you would need the butt connectors (crimp both ends). The kit I linked to only contains a couple, so you might find it better to buy the tool and connectors separately. But I don't think it would be very satisfactory.

To repeat though - DO NOT OPEN THE PSU CASE UNLESS YOU ARE ABSOLUTELY CONFIDENT THAT YOU KNOW WHAT YOU ARE DOING AND HOW TO OPERATE ON HIGH ENERGY CIRCUITS SAFELY

[c.ruel]

Thanks peterb. I think I will do the thing were i cut the cables resolder them, heat shrink them and then sleeve. All the sleeving and that looks really cheap ... just the soldering iron is expensive. Thought I might as well get a tool kit with a soldering iron in it so I can get all the proper tools, it's like £27, which is reasonable for what you get but still annoying just to shorten some cables and sleeve them ... although I will obviously get alot of use out of the tool kit and they are useful to have.

Anyway as I said before thanks for the advice peterb, one last thing do you think this soldering iron will be good for the job, do I need anything else that isn't in that tool kit (other than the heat shrink and sleeving obviously).

[malfunction]

Have you looked at simply chopping out the cables / connectors you don't need?

i.e. if you have a cable with 4 'molex' connectors on it that's too long and you only need 2 of those just chop the others off (neatly and / or with a bit of insulating tape)...

Works really nicely with most SATA power connectors as they are usually the inline / crimp on type rather than being a 'junction' for two separate lengths of cable. SATA power connectors are also really easy to take apart and crimp onto another part of the cable without breaking anything

[Pob255]

Crimping is a methord of connecting a wire to a plug without soldering.

You could get a crimping tool like peterb linked to and some of these molex plugs
http://cgi.ebay.co.uk/Male-Molex-Plu...60de60ffdc0340

However self-crimping plugs would be better, the problem is finding them.
They are normally right angled connectors, this looks like it's the self crimping type.
http://www.kustompcs.co.uk/acatalog/info_1968.html

There's a good guide here http://gam.net.au/pcmods/satapower/1.html on taking apart sata plugs, again would be better if you could buy some of the self crimping type, as they are easy to damage trying to get them apart.
good image here of a self crimping sata plug


Good luck if you try to hunt these things down. And tell us if you're successful because, I for one, would like to know where I can get my hands on them.




You could use terminal block to join lengths of wire together but that would probably end up damn messy



Here we go found some molex self crimpers
http://www.chilledpc.co.uk/shop/prod...oducts_id=1126

Cannot see any sata self crimpers on chilledpc, best bet would be to contact them and ask.

[malfunction]

Kustom PCs has the SATA connectors Pob mentions and a few other bits besides:

http://kustompcs.co.uk/acatalog/Kust..._Molex_66.html

If you can figure out exactly what you're looking for Toby Electronics may be cheaper (I can find crimp-on 'molex' connectors - pins sold separately - but no SATA ones on that site):

http://www.toby.co.uk/content/catalo...px?category=23

[peterb]

I'd go for this iron

http://www.maplin.co.uk/Module.aspx?ModuleNo=4056 (possibly with an optional larger bit for soldering the cables) or this

http://www.maplin.co.uk/Module.aspx?ModuleNo=4063

Which is a little more powerful and has the larger bit fitted.

If you haven't soldered before, practice first!

On a technicality, the links and images) pob255 refers to are not crimp type connectors - they are standard idc (insulation displacement connectors). The tines on the end of the connector pierce the inulation on the cable to make the connection. They are designed for relatively low current operation (and for speed of assembly in a mfr environment). The main connectors for a mobo don't use idc connectors because of the current involved - they are true crimp connectors (again used for speed of assembly during manufacture)

[Pob255]

they are standard idc (insulation displacement connectors).

That's what they are called, which is always the issue when trying to find these things, you know what you want but not what it's called.
That and manufactors calling the same things by different names just to make their "product" stand out and so confuse us.

While they are not designed for massive loads, almost every thing you plug a sata or molex into doesn't demand massive loads.
For the things that do, motherboard and graphics cards, they don't make IDC for, you have to get true crimp type.

Again we have a problem as I have no idea what the correct name for the suqare cross section pins used in both pci-e and motherboard power plugs are called, which makes them almost inpossible to search for.

Does anyone know what they are correctly called?

[malfunction]

I have no idea what the correct name for the suqare cross section pins used in both pci-e and motherboard power plugs are called, which makes them almost inpossible to search for.

Does anyone know what they are correctly called?

The official name appears to be "Mini-Fit Jr":

http://www.molex.com/molex/products/...key=minifit_jr

More googling seems to indicate that the ATX / mobo plugs are standard "Mini-Fir Jr" but that the *6 pin* PCI-E connector is a non standard version of one:

"The ATX connectors are easy to get. The 4 pin 12 volt, 8 pin EPS 12 volt, main 20 pin, and main 24 pin are all Molex mini-fit jrs. You can get those just about anywhere. The part numbers are on this page. Watch out for the 6 pin PCI-Express. It looks like a 6 pin mini fit jr. but it actually isn't. It's really a special, modified mini-fit jr. which is keyed differently."

Also before anyone asks 'floppy' power connectors are berg connectors...

http://en.wikipedia.org/wiki/Berg_connector

[Pob255]

Ahh that's what they are called.

If you're just trying to reduce the length of existing cables then you can reuse the sockets on it's the pins that you have to get if you where just planning on crimping them
from the looks of the pictures its the 5556 Female Terminal's you want for the psu.

ps thanks, http://www.playtool.com/pages/psunonpc/nonpc.html is a really handy website

[c.ruel]

Sorry for bringing this topic up again so late after the replies but I have been really busy lately.

Basically I don't use any of my 4 pin molexs and the only thing I can see myself using them for are fan controllers and fans in the future, which I doubt use very much power or are that fussy. My over cables aren't too bad, all there are quite a few excess sata ones.

My 4 pin molex cables all have more than one connector on them and really I only want one connector on each cable so I want to do what malfunction suggested and chop the other connectors off, my only question is how do I seal the exposed end up, do I use some sort of tape or what?

I think I will do that in the interim period before I get a soldering iron and do what peterb suggested, one my exams and stuff are over.

Thanks loads everyone for all the suggestions.