How To Make Ethernet Cables

Need a 5-inch straight-through Ethernet cable? A 37-foot crossover cable? Tired of miles of extra cable coiled around your desk? Sure, you could probably buy custom cables online, but with a spool of Cat5 and a $10 crimper you can make your own, for less.

 

Most networking devices ship with Ethernet cables that let you connect the hardware to your network. Many of these cables, however, are at a fixed length usually measuring no more than four feet. That lack of length doesn't present many placement options for devices that are not portable and usually are hard-wired to a network such as routers, switches, servers and NASes.
Of course, you can purchase longer Ethernet cables from Best Buy and other electronic/computer stores. Buying pre-made Ethernet cables is the most practical option if you have a couple of devices to setup on a small or home network. But what if you are responsible for a large network, or several networks, as a small-business tech consultant? Or, what if you need a super long cable that you just can't find in the store? The answer is simple: Make your own cables. Ethernet cables (also known as RJ-45, patch, and network cables) are easy to make with a little practice and the right tools.
Even with modest cabling needs, you can reach the break-even point and pay off the small investment you'll need to make your own Ethernet cables. At Best Buy, for example, a 6-foot Cat5 network cables costs $19.00; a 25-foot cable is priced at around $33.00 and for a 50 foot cable, the price is $43.00. These prices are just for one cable. Researching several online distributors, you can buy a spool of 1,000 feet of Cat5e from $65-$120.00 and the "heads;" the modular plugs used to terminate an Ethernet cable, can be easily found in 50-count bags for under $10.00. The crimping tool you also need is a one-time start-up cost of anywhere from $10-$50.00 depending on the quality and additional features that the crimping tool may have.
Sure, it'll take a little extra time to make your own Ethernet cables, but you'll save money, you'll have cables that are the exact right length, and you might just have some geeky fun, too.


Step 1
Determine which type of cable you need. Newer networking hardware, adapters, NASes, switches and routers are connected with what's called a straight through cable. This is the type of Ethernet cable that generally ships with today's networking devices. In some cases you'll need a cross-over cable for , connecting older devices by their switches switches or connecting two hubs (a technique called daisy-chaining), or connecting two older laptops to each other (for file transferring, for example. Cross-over cables are rarely needed for networking hardware that's only about three or fours years old, thanks to a technology known as Auto-MDIX, which can automatically sense on network ports if a straight through or cross-over connection is needed and will make the appropriate connection. However, if you want to link older equipment, check your device's documentation to see if the connection requires a cross-over cable.

Step 2
Get the right tools. You will need a spool of Cat5 (Cat5e is now the standard) or Cat6 (if your network is Gigabit Ethernet) cable. Cat5 or Cat6 cable can have plenum or PVC jackets. PVC cable is cheaper, but it also releases a toxic smoke if it catches on fire, so some building codes prohibit it. Plenum, on the other hand, does not release these toxic fumes. If you have no prohibitions preventing the use of PVC and are new to making Ethernet cables, your best bet is to start with PVC coated cable. It's cheaper and easier to work with because the wiring is not as soft as a Plenum cable's. You'll also need RJ-45 plugs or "heads" plastic modular plugs that terminate both ends of the cable, a wire cutter (or a good, sharp pair of scissors), a wire stripper and an RJ-45 crimper. The crimper is used to secure the heads at each end of the wire. You can purchase crimpers, cable and plugs from a slew of online stores or Radio Shack.

Step 3
Cut the wire to the desired length and strip about an inch of the jacket off, exposing the four twisted pairs of inner wiring. When stripping the cable, be careful not to nick the wires. This can cause problems with the connection. Do this at both ends of the cable.

Step 4
Prepare your wire for termination or "crimping". Untwist the wire. Arrange your wires based on whether you need a straight through or crossover cable. For a straight through, arrange the wires, on both ends as you are holding and looking at the cable, from left to right: white-orange, orange, white-green, blue, white-blue, green, white-brown, brown. For a cross-over cable, the wire arrangement is different at both ends. At one end, arrange as follows: white-green, green, white-orange, blue, white-blue, orange, white-brown, brown. At the other end, arrange as you would for a straight-through cable: white-orange, orange, white-green, blue, white-blue, green, white-brown, brown.
 Step 5
Terminate the cable at both ends. Straighten the wires out as much as possible; it will make them easier to place inside of the RJ-45 plug. Get the wires as close to one another as possible, holding them between your thumb,index, and middle fingers. Trim the wires down evenly to about a quarter of an inch. Here's the tricky part that may take some practice: slip the wires inside of the RJ-45 plug with the clip-side down. Don't try to jam the wires in, they should slip inside the clip and fit snug. You don't want to see any wires between the plug and the jacket; you want just a bit of the jacket going into the plug. You also want to make sure each wire is making contact with the gold leads in the plug. Take the crimper and crimp down on the plug, pressing the crimper firmly, but not too hard.

Step 6
Take the crimper and crimp down on the plug, pressing the crimper firmly, but not too hard.

Step 7
Test the cable. Connect a networking device with an LED indicating network activity to your network using the cable you created. Ensure you are getting a strong signal. /pcmag/