Making & Mending - DIY Ethernet Cables
Ethernet is one of the most important types of cables today, being used to connect all manner of technology around the world to the Internet. While many stores today have pre-made ethernet cables available, sometimes another option is needed. Users may need a cable in an unusual size or just need to replace a broken connector. This guide will show users how to put an RJ45 connector onto the end of bare ethernet cable.
Before jumping into the main guide, there is an easy fix if you have a connector where the release tab broke off. When the tab breaks, the cable will not lock into place and have trouble maintaining a connection. This can be easily fixed with a Quick Snap Latch, which is a much easier repair than replacing the whole connector. If a broken latch is the only issue, grab one of those for a simple repair that will only take a few seconds.
A video guide detailing the below steps can be found at the bottom of the article.
Step 1: Gathering the Supplies
There are a few simple supplies that will be needed for an installation or repair. The key components are the bare ethernet cable and the RJ45 connectors. Beyond that, just a few tools are needed. A cable stripper and modular crimper are essential in any scenario. A pair of small scissors can also be handy for trimming away any excess wire. Testers can also be useful once a cable is assembled/repaired to make sure it works correctly. Testers are also great for pinpointing the exact problem with a damaged cable, such as identifying a specific wire inside the cable that is faulty.
Step 2: Stripping the Jacket
Take the cable stripper and spin it around the outside jacket. Higher-quality strippers will have pre-set depths, so they cannot cut too deep and damage the wires. Other strippers may run the risk of cutting deeper. Be sure to not cut too deep or the internal wires could be damaged. If that does happen, cut the end off the cable and try again. After the jacket has been cut, pull the end off to access the individual wires inside the main cable.
Step 3: Separating the Wires
The individual wires inside the cable should be twisted together in pairs. Untwist each pair so each wire lays out individually. If a lot of wire is coming out of the end, use some scissors to cut off the extra length. The remaining wire should be just long enough to fit inside the RJ45 connector.
Step 4*: Attaching the RJ45 Connector
*See Appendix A for wiring diagrams
When inserting the wires, each metal core (called conductors) on the individual wires must touch the metal bits (called contacts) in the RJ45 connector. There are different ways that ethernet cables can be wired. The two main color-code patterns (called pinouts) are T-568A and T-568B, with T-568B being the more common of the two and the one shown in the image below. Pictures of the other pattern and additional details about pinouts can be found here.
Step 5: Crimping the RJ45 Connector
Insert the RJ45 connector into the crimp tool and squeeze tightly to ensure the connector is firmly attached to the cable.
(Optional) Step 6: Testing the Ethernet Cable
Insert the ethernet cable into the tester and press the start button to begin the test. If all the lights turn green, the cable is fully functional. If one or more lights turn red, that specific conductor is not making a connection. In the event the cable fails, one of two main issues could be occurring. The first is that the failing conductor is not touching the contact. This can also happen if they are not touching enough, making the signal too weak to work. If that happens, cut off the connector and try again.
The other potential issue is damage to the cable. If a cable has a kink in it or was bent too much, the conductors can be damaged and become unusable. The damage may be visible from the outside, in which case the damaged part of the cable must be cut off. If doing this would make the cable too short or if the damaged spot cannot be located, the cable will have to be replaced instead.