How to Crimp Ethernet Cables: Snipping and Stripping

We live in an increasingly do-it-yourself world. We can check out our own groceries, pump our own gas and diagnose our own — OK, maybe not that last one. But for the do-it-yourself type, making your network cables is no problem. These days, ready-made Cat 5 cables — the standard kind used for most Ethernet networks — are relatively easy to find at most electronics stores at reasonable prices. So why assemble your own network cables? It may not be something you do everyday, but having the supplies and know-how to whip up a network cable on the spot can be very handy.

Perhaps you want to run custom lengths of cable, whether very short or very long. After all, coiling a 25-foot cable when you need only two feet seems kind of silly, not to mention a decorating don’t. On the other hand, if you want to route 50 feet of cable upstairs through a closet ceiling, you can minimize your drill hole by fishing through bare ends and crimping on your connectors later. Or, maybe you just need a network cable right now and it isn’t convenient to run to the local electronics depot. �With 1000 foot spools of bulk cable running under $40 on eBay, it requires little investment to keep a supply on hand.

Even if you’re like me and wind up turning most do-it-yourself handyman projects into some kind of exotic folk art, assembling a network cable is surprisingly easy. With a little practice you can finish the job in less than ten minutes.


Bulk Cat5 Cable, RJ-45 Plugs, and Crimper
Bulk Cat5 Cable, RJ-45 Plugs, and Crimper

You need Cat 5 cable, of course. You can buy it in bulk at electronics stores and online. Or if you already have some cable with damaged connectors, snip them off and start anew. Cat 5 comes in a wide variety of jacket colors, but is most commonly found in blue – use any one you like.

You also need RJ-45 connectors – the plastic plugs at the end of the cable. You can also find these at many electronics stores in packs of 25, 50, or 100, often for less than $10.

Most off-the-shelf network cable uses stranded wires, but solid wires are also available and ar sometimes preferred for long or in-wall runs. Check with the vendor to ensure that your RJ-45 connectors are compatible with your stranded or solid cable — some connectors accommodate both while some do not. A mismatch could cause unreliable performance.

Finally, you need a crimping tool that supports 8-conductor modular plugs, sometimes also called an RJ-45 crimper. Radio Shack’s “Professional Crimping Tool” (Item #279-405) will do the job for $33, but you can find equally good solutions for half that price on eBay and at online retailers.

Step 1

Grab one end of the cable and, if necessary, snip it to get a straight cut. You need to strip off about one inch of jacket. If your crimper has a jacket stripper, simply shove the cable end into the stripper until it stops, squeeze the crimper gently, and twist the cable as the razors slice through the jacket. Remove the cable and pop off the cut end of jacket. Strip 1 inch of cable jacket
Bundle of twisted pairs

Step 2

With the jacket stripped, you’ll find four twisted pairs of wires. Each pair is represented by a solid color and a striped color each of brown, green, orange and blue. Separate these pairs so they are unbundled.

Four twisted pairs

Step 3

Now separate the pairs, so that you have eight individual wires. Using nimble figures, arrange the eight wires into the exact sequence represented in the wiring diagram labeled 568B.

It can take some practice to configure the wires into sequence. They can be unruly and need some twisting. You want the wires to be as close together as possible. Sometimes it helps to flex the wires lightly to better manipulate them into position.

This wiring sequence, known as 568B, is the most common arrangement for Ethernet cable.

568B Wiring Diagram