I've been doing a bunch of cat 5 running lately. I've been putting RJ45 ends on everything I run.

I'm finding it is still not that easy for me to get the little wires into the connectors. Do any tools or techniques exist for helping get them into the connector? I already have a tool to crimp the ends but it's the actual getting of the 8 little wires into the connectors that I'm looking for help.

6 Answers 6


I'm not aware of a tool but I'll give my tips.

General Process

  1. Strip the jacket 2-3 inches back. Jacket strip tools are great for this:  a knife works but it takes longer and you're more likely to nick a wire (= start over) or accidentally cut yourself.

jacket stripper

  1. If you're using a boot, install it now.

  2. Splay the wires out, unwinding them, and start lining them up in order as you go. Try not to unwind any further back than you've stripped the jacket. Hold them tightly and flat with one hand while you do this.

enter image description here

  1. Keep holding the wires flat, but with your other hand, flex them back and forth a bit to get them 'seated' (to relax in this position). The idea is when you let go, they'll stay lined up and barely move (but don't let go until you cut them). This is much easier when you're using solid conductor cables (mainly in-wall type cables) as opposed to stranded conductor (used for patch cables).

  2. Use a pair of side cutters to trim the wires to the correct length, about 1/2". Do this in a single cut, and make sure it's a straight cut so all the wires are the same length.

  3. Push the wires into the connector. This is basically the first time you let go since lining them up. You want the wires to go to the very end (red arrow), and the jacket to be seated underneath the block that crimps down onto it (blue arrow).

seated rj45

If the jacket is cut too far back, the connector won't crimp onto it, and the only thing holding the connector on will be the wire connections. While it might work for a bit, these wires are easy to break, sometimes in a non-obvious way because only a single wire fails.

  1. Use a tester to verify it's good. The ones with indicators on both ends can be had for tens of dollars. It's much easier to fix if you find out it's wrong immediately, plus it helps teaches immediately what you're doing wrong.

Cat5 tester

Another tip:  don't crimp them if you can help it! :)

Punchdown blocks on patch panels and keystone jacks are easier to do properly (especially for cat 6), and can make a nicer installation.

Patch cables (any short-ish run that doesn't go through the wall) are cheaper to buy assembled than you can buy the parts for (even with bulk cable and connectors and valuing your time at $0/hr), and the cables are better than what you can do by hand. Since stranded cable is also harder to assemble, avoiding assembling patch cables means you avoid stranded cables.

That said, many years ago in the late 1990s I spent an evening watching TV and creating a couple dozen ~1.5' patch cables for my dad's office network, and that was a pretty good crash course. Since then I've rarely screwed one up. :)

Really, it's just practice. For example, I'm a non-pro, doing a few cables/ends here and there, and every few years it seems I do a bigger job like networking a house, but then I go months between doing anything. I can crimp an end in under a minute for sure, and faster as I get back into the swing of it.

  • 2
    Before step 2: put the boot on if you're using them. Jan 10, 2017 at 16:50
  • 1
    I've found that cutting the jacket away and then pulling the string down to cut the jacket a few more inches helps immensely. And then it doesn't matter if you nicked any of the wires when cutting the jacket initially, as that part will be cut off. Uses a bit more cable, but cable is cheap :) That said, punchdowns are much easier as you said, especially for novices, and patch cables are cheaper to buy than to build yourself.
    – mmathis
    Jan 10, 2017 at 17:37
  • 4
    Ah, that's usually step 6: Realize you forgot the boot, cut the newly-crimped end off, install the boot, and go to step 1. But your way is better :)
    – gregmac
    Jan 10, 2017 at 17:37

CAT5 cable is available in both stranded and solid conductor forms.

Solid conductor cable is for in-wall installation and longer runs. Stranded cable is for the drop-cables at either end of the run. The total length of the run should be no more than 90meters, with 5meters allowed at either end for drop cables.

Solid conductor cable is designed to be punched down, using a tool similar to the following;

Punchdown tool

The ends of your solid run should be into patchbays or receptacles; they are not designed to be terminated on CAT5 plugs

CAT5 Receptacle

The CAT5 terminators you're making are used on the short drop-cables which connect equipment to the patchbays or receptacles. Stranded cable is much easier to put into order by hand, or you can buy them in bulk off Amazon etc for less than the cost of the tools.

  • 1
    Actually this is solid. But it needs ends because of the box it's going into. This box essentially has what amounts to an RJ45 turnaround in it. It's designed to be on the floor or lower on the wall. If you bang something into it and break it and need to replace the box, that's all you have to do. You plug in an RJ45 on the inside of the box too, so you can easily remove it and replace the box.
    – lightbord
    Jan 10, 2017 at 18:15

A far easier way is not holding cable in your hand. Instead use a little hobby vise to hold cable tightly. Pinching it helps flatten out the bundle. Be patient laying out wires while they are two inches long. Avoid having wires wrap around each other. Lay them out as flat as you can. Use tweezers to arrange. Some wires don't have a continuous tracer color, so redo with colored Sharpies. Having the vise hold the cable after the wires are laid out and cut makes it easy to slide the connector on. Some cables are easier with 5/8 inch wire exposure rather than half-inch. Check carefully before crimping. Look in the end of RJ45 with strong light to confirm all wires are well seated.


Another thing that might be helpful is a feed-thru type connector:

CAT5 feed-thru connector

I say "might" because it's still tricky to get the hang of. At least with these you can be sure your wires were pushed all the way in.

I learned through trial and error not to cut too much of the jacket off. Only remove 1.5 to 2 inches. The individual wires tend to bend and kink if they're too long. It's easier to push them all together holding the jacket after you get them positioned correctly.


The closest thing I can suggest to automatically easing the process would be to use Cat6 style connectors, which are easier to get the wires into, in my experience, due to the way they are designed. Cat 5e connectors the wires are 8 flat across, and it can be tricky to get them all lined into the right slot without crossing up or one coming out short. Cat6 are 4 up, 4 down, so if you get it in the right hole at the back of the connector, it's much harder for it to cross up as you push it home.

I generally don't do that myself, but I've been doing Cat5 since long before there was Cat5e or Cat6...

The part that plugs into the jack is the same on both types.


My method for RJ45 Cat6 - I use an alligator clip with a round wire feed to untwist the pairs, I NEVER pull the pairs to a 90 degree angle when separating them. Avoid bending the pairs in any other direction except for straight out towards the connector - any bend becomes a "spring" when you go to put the whole thing into the connector holes. I make a 3/8" cut down the cable after untwisting and clip the wire pair separator below the top of the cable jacket. Straighten the wires one at a time with the basic plastic cable sheath cutter and then all together the same way. Once I get the pairs lined up like 865 - B configuration I use forceps to hold them in place and slide the mess into the RJ shell. I use forceps to avoid having to change my grip on the neatly trimmed pairs, letting go at this point causes a complete do-over and a definite time killer. If I've made a mistake or a wrong wire makes its way into the wrong slot I still have the colors lined up with forceps and still have a clean 90 degree cut - I make the needed change after making sure there is no "spring" tension acting on the errant wire and then crimp it. A nice clean cut with a real sharp blade makes it easier. A 30 power lighted magnifier comes in handy for old timers like me. good luck!

Not the answer you're looking for? Browse other questions tagged or ask your own question.