How To Remove Molex's?

moving shadow · Post by **moving shadow** » Mon Dec 01, 2003 6:26 pm

Well in a week or so i am going to either use some heat shrink or cable braid to tidy up the new PSU im getting....i know you can get the molex's off with a pin or something, but is there any tool you can buy that can make this process simpler?

cheers

Seal · Post by **Seal** » Mon Dec 01, 2003 6:36 pm

yep i tried an interesting method today actually. Get a standard bic biro pen, remove the inner ink tube and use that. Basically push it over the molex male pin and when pushed down hard will go over the 2 latches and push them in, easily removing the pin from the connector.

moving shadow · Post by **moving shadow** » Mon Dec 01, 2003 7:18 pm

thats bloody genius thinking m8...cheers!

lenny · Post by **lenny** » Tue Dec 02, 2003 12:37 am

Wish I'd known that before I bought the molex extraction tool. I picked one up from Radio Shack, might be similar to the ones sold at other places. Worked OK for the pins on the PSU side, but when extracting the other type (the ones that plug into the connectors on the PSU side) it has a tendency to bend the little tabs, and you need to straighten them out with a pair of pliers. And the tabs break easily, so whatever method you use, don't apply too much force.

Zyzzyx · Post by **Zyzzyx** » Tue Dec 02, 2003 12:41 am

Any tips for removing the wires from the 20 pin m/b power connector? Would be much easier to get sleeving on that bundle of wires if I didn't have to slide it over the monster sized connector. I can do it, but not with as small-sized sleeving as I'd like to.

Ginta · Post by **Ginta** » Tue Dec 02, 2003 3:51 am

I use a hobby knife (x-acto blade) to extract molex connectors. It takes a little skill and twisting the wire in the housing to bend the tabs in. Using the sharp point I can easily bend the tabs back out once I remove the pin. I've made many molex Y power cables into 7v adapters this way.

Haven't tried removing the PSU atx connector yet though.

Post by **Ralf Hutter** » Tue Dec 02, 2003 5:50 am

Zyzzyx wrote:Any tips for removing the wires from the 20 pin m/b power connector? Would be much easier to get sleeving on that bundle of wires if I didn't have to slide it over the monster sized connector. I can do it, but not with as small-sized sleeving as I'd like to.

I'm too freaked out to try and keep track of where each of those 20 wires goes (assuming that I could even figure out how to get them out of the connector) that I looked around and found "4x" heatshrink tubing. Regular heatshrink is "2x" meaning that it shrinks to 1/2 it's original diameter. I found that you can buy 4x tubing that shrinks to 1/4 of it's original diameter. I got some 2.5" or 3" 4x tubing and just did it that way. Kept me from having to hassle removing the 20-pin Molex. The only problem is that this 4x stuff is real hard to find in short lengths and I can't even find the name of the place I bought it from to link for you guys.

Seal · Post by **Seal** » Tue Dec 02, 2003 11:56 am

Ralf Hutter wrote:
Zyzzyx wrote:Any tips for removing the wires from the 20 pin m/b power connector? Would be much easier to get sleeving on that bundle of wires if I didn't have to slide it over the monster sized connector. I can do it, but not with as small-sized sleeving as I'd like to.
I'm too freaked out to try and keep track of where each of those 20 wires goes (assuming that I could even figure out how to get them out of the connector) that I looked around and found "4x" heatshrink tubing. Regular heatshrink is "2x" meaning that it shrinks to 1/2 it's original diameter. I found that you can buy 4x tubing that shrinks to 1/4 of it's original diameter. I got some 2.5" or 3" 4x tubing and just did it that way. Kept me from having to hassle removing the 20-pin Molex. The only problem is that this 4x stuff is real hard to find in short lengths and I can't even find the name of the place I bought it from to link for you guys.

Same here!!!! Took me about an hour last night of fiddling but i finally found out how to do it, essentially its the same as a molex connector with 2 tabs either side of the connector. You have to find a very very thin screwdriver to slide down the side and push these tabs in. Once thats done you have to pull the wire but you have to pull quite hard!!! which is what i got stuck on for ages! i didnt think you had to pull on them as i thought they'd fall out like molex ones do. tug quite hard though and they'll snap out, youll realise why you have to tug quite hard once you put them back in as they snap back in quite solidly. Im a little hesitant on doing my psu although ive wanted to for a while because to do 20 of those wires seperately would take me hours! probably a 1/2 a day jobby.

Try it on an old psu first to get a feel of how it should be done. You can buy a tool for it, ive seen them in american shops but theyre quite expensive if i recall correctly.

Seral

HammerSandwich · Post by **HammerSandwich** » Tue Dec 02, 2003 12:43 pm

Ralf Hutter wrote:The only problem is that this 4x stuff is real hard to find in short lengths and I can't even find the name of the place I bought it from to link for you guys.

I've never used them, but you could try here. Mmmm, Google!

Post by **Ralf Hutter** » Tue Dec 02, 2003 12:46 pm

Seal wrote:
Ralf Hutter wrote:
Zyzzyx wrote:Any tips for removing the wires from the 20 pin m/b power connector? Would be much easier to get sleeving on that bundle of wires if I didn't have to slide it over the monster sized connector. I can do it, but not with as small-sized sleeving as I'd like to.
I'm too freaked out to try and keep track of where each of those 20 wires goes (assuming that I could even figure out how to get them out of the connector) that I looked around and found "4x" heatshrink tubing. Regular heatshrink is "2x" meaning that it shrinks to 1/2 it's original diameter. I found that you can buy 4x tubing that shrinks to 1/4 of it's original diameter. I got some 2.5" or 3" 4x tubing and just did it that way. Kept me from having to hassle removing the 20-pin Molex. The only problem is that this 4x stuff is real hard to find in short lengths and I can't even find the name of the place I bought it from to link for you guys.

Same here!!!! Took me about an hour last night of fiddling but i finally found out how to do it, essentially its the same as a molex connector with 2 tabs either side of the connector. You have to find a very very thin screwdriver to slide down the side and push these tabs in. Once thats done you have to pull the wire but you have to pull quite hard!!! which is what i got stuck on for ages! i didnt think you had to pull on them as i thought they'd fall out like molex ones do. tug quite hard though and they'll snap out, youll realise why you have to tug quite hard once you put them back in as they snap back in quite solidly. Im a little hesitant on doing my psu although ive wanted to for a while because to do 20 of those wires seperately would take me hours! probably a 1/2 a day jobby.

Try it on an old psu first to get a feel of how it should be done. You can buy a tool for it, ive seen them in american shops but theyre quite expensive if i recall correctly.

Seral

I actually cut off the end of a couple of junker PSUs so I could practice doing this but I can't come up with a decent way to keep track of which wire goes where. Ya got 7 black wires, 3 or 4 red wires and 3 orange wires that must have a specific location but how do you tell them apart once you've disconnected them from the connector??

silvervarg · Post by **silvervarg** » Tue Dec 02, 2003 1:56 pm

Ralf:
I can't come up with a decent way to keep track of which wire goes where.

How about marking the wires with a permanent pen?
Preferably high up so marking will be covered once your done.
In addition to the markings you would need to write down the order of the wires, since the marking is just to keep a few same-color-wires apart.
Or if you don't want any markings left once your done use something that you can remove as a marker. E.g. cable-straps

lenny · Post by **lenny** » Tue Dec 02, 2003 2:41 pm

Ralf Hutter wrote:Ya got 7 black wires, 3 or 4 red wires and 3 orange wires that must have a specific location but how do you tell them apart once you've disconnected them from the connector??

Do you know that they must be in a specific location? I've opened up some PSUs, and found that, for example, the black ground wires all terminate on the same spot on the PCB within the PSU. When putting 4 pin molex back together, I never bothered with which black goes into which hole, and never had a problem. Never did it to the motherboard connectors, though

Considering that most PSUs are assembled by semi-skilled workers in developing countries, I find it hard to believe that they need specific locations for same colored wires.

Which brings to mind the question - why so many wires for essentially 8 different types of signals? Redundancy? Load distribution? A quick search on the web shows that 18 AWG wire (on a PSU I can examine right now) can carry about 16 amps of current. Some other sites suggest much lower figures, but for longer runs (15 ft).

I've came across (somewhere in this forum, if memory serves me) power supplies that claim to have discrete circuits for hard drives and motherboard, I think. But even then, it will just mean different circuits for molex vs. 20 pin MB / 4 pin ATX connectors.

Edit: Best picture of the internal of PSU I could find on SPCR is this one. Doesn't really show the details of the connection though.

Inexplicable · Post by **Inexplicable** » Tue Dec 02, 2003 3:03 pm

Ralf Hutter wrote:Ya got 7 black wires, 3 or 4 red wires and 3 orange wires...

Cut the blue wire! Cut the blue wire!

Errm, yeah. Label the wires.

All you need is white painters tape and a pencil.

Post by **Ralf Hutter** » Wed Dec 03, 2003 6:27 am

err, um..if the wire bundle is going to be covered with a piece of flexo wrap and a couple of pieces of unshrunk heatshrink where am I supposed to put these labels?

eeeeeee...., too much thinking for this spudboy, I think I'm just going to order a Dell and be done with all this trick stuff. See ya in the "Prebuilt forums..."

rhyuso · Post by **rhyuso** » Wed Dec 03, 2003 2:45 pm

I should think that the reason for the multiple wires from the PSU to the mobo connector is due to trying to decrease the impeadance of the connection.
Not to get too technical, but if things are swiching fast and there is too much inductance then you get nasty spikes and stuff. This is in essence why a ground plane is (pretty much) necessary on any digital circuit board.

A large quantity of wires usually power and ground or large PCB tracks for ground and power are often used. At least they are in the avionics I help to design