How To Strip Electrical Wire

Stripping electrical wire is an essential skill for many DIY home projects and repairs. Whether you’re replacing a light switch, fixing a lamp, or working on more complex electrical tasks, knowing how to strip wire properly ensures safe and effective connections.

In this guide, we’ll show you how to strip various types of electrical wire, introduce you to the necessary tools, and provide expert tips to help you master this fundamental electrical skill.

What You Need to Strip Wire

A true multi-tool, wire strippers are essentially spring-loaded pliers with different-sized notches cut into their jaws. Their primary function is to cut and remove the plastic insulation from solid or stranded copper electrical wire without cutting the wire itself. This feature allows you to attach the wire to a terminal or wire-nut it to another wire.

You can also use them to cut, bend, and pull wire. Many models can even cut small screws to length, which allows you to secure outlets and switches into electrical workboxes without damaging the screws’ threads.

Take a stroll through your local hardware or big-box store, and you’ll find basic wire strippers along with more specialized models that can crimp terminals, strip insulation from coaxial cables, and even cut and remove waste insulation in one motion.

Understanding Electrical Wire Basics

Before diving into the stripping process, we strongly recommend having a firm grasp of the basics of electrical wire. This knowledge will help you choose the right tools and techniques for your specific project.

Types of Electrical Wire

Electrical wires come in several varieties, each designed for specific applications. Recognizing the different types will help you select the proper wire for your project and ensure safe, effective connections:

• Coaxial cable: Found in TV and internet lines.
• Lamp cord: A flexible, two-conductor wire for light-duty appliances and extension cords.
• Nonmetallic (NM) cable: Commonly known as Romex, this is the most common residential wire.
• Solid core wire: A single, thick copper conductor standard in household wiring.
• Stranded wire: Features of multiple thin copper strands, popular for applications in which flexibility is necessary.

Wire Gauge Explained

The American Wire Gauge (AWG) system measures wire gauge according to thickness. The lower the AWG number, the thicker the wire.

Standard household wiring typically uses 14 AWG or 12 AWG for circuits. Understanding wire gauge is crucial for selecting the appropriate stripping tool and ensuring proper electrical connections.

Essential Tools for Stripping Electrical Wire

Having the right tools makes wire stripping easier, safer, and more efficient. Let’s explore the primary tools used for this task.

Wire Strippers

Wire strippers are the most efficient and safe tool for removing insulation from electrical wires. These specialized pliers feature notched jaws designed to cut through insulation without damaging the underlying wire. Most wire strippers can handle a range of wire gauges, typically from 10 to 22 AWG.

When choosing wire strippers, look for models that meet the following criteria:

• Accommodate the wire gauges you commonly work with
• Feature comfortable, ergonomic handles
• Perform additional functions like wire cutting and crimping

Alternative Tools for Wire Stripping

While dedicated wire strippers are ideal, you may need to strip wire without this specialized tool. In such cases, you can improvise with the following tools:

• Needle-nose pliers: Gently grip and pull the insulation off the wire.
• Scissors: Use the notch near the pivot point to carefully cut the insulation.
• Utility knife: Carefully score the insulation around the wire, then pull it off.

Remember, these alternative methods require extra caution to avoid nicking or cutting the wire.

How To Strip Wire

Now that we’ve covered the basics let’s talk about how to strip wire like a professional. Different types of wire require slightly different stripping techniques for the best results. 

Stripping Nonmetallicic (NM) Cable

First, you’ll have to remove the outer cover and insulation from the wire. Here’s how:

1. To strip NM cable, first, you must cut away the outer jacket to access the conductors. It’s important not to cut or nick the conductors beneath the jacket, but there’s a tool called a L’il Ripper Stripper that cuts the jacket without damaging the conductors. It can also tighten twist-on wire connectors (popularly known as wire nuts) and twist and loop wire. You can also use a utility knife to cut the jacket, but again, you have to be careful not to nick the conductors’ insulation.
2. Place the cable on a flat surface and cut carefully along the length of and between the conductors to expose the required length of the conductor.
3. Pull the jacket away from the conductors and cut it off. Once the jacket is off, determine the length of insulation you want to remove. (For most applications, about 1 inch is adequate.)
4. Insert a conductor into the proper-sized notch in the stripper’s jaws, squeeze the handles, and pull it away from the wire.

Stripping Coaxial Cable

Coaxial cable is slightly more complex due to its construction. Here’s a quick guide:

1. Use a coaxial cable stripper for precise cuts.
2. Strip the outer insulation to expose the braided shield.
3. Carefully unbraid the shield to access the inner conductor.

Stripping Lamp Cord

The procedure for stripping the lamp cord is exactly the same as for NM cable, except there is no sheathing to remove. To prevent cutting into the strands, first, do a test on a scrap to determine the wire’s AWG.

Stripping Solid Core Wire

Solid core wire, commonly found in household wiring, is relatively straightforward to strip. Just follow these three steps:

1. Choose the correct notch on your wire stripper.
2. Clamp the wire stripper onto the insulation at the desired strip length.
3. Twist and pull to remove the insulation cleanly.

Stripping Stranded Wire

Stranded wire requires a gentler touch to avoid damaging the individual strands. We recommend taking these steps to strip it:

1. Use a wire stripper with a precise notch for the wire gauge.
2. Apply less pressure when clamping the stripper.
3. Gently pull the insulation away, being careful not to separate the strands.
4. If necessary, twist the exposed strands together after stripping.

Safety Precautions When Stripping Electrical Wire

Safety should always be your top priority when working with electrical wires. We strongly recommend taking the following precautions.

Proper Insulation Removal

When removing insulation, always strip just enough to make a proper connection, as over-stripping can expose wire beyond the connection point. As a final check, ensure no stray wire strands remain outside the connection.

Avoiding Wire Damage

To avoid damaging the wire, use the correct-sized notch on your wire stripper—otherwise, you could nick the wire. When using a utility knife, score the insulation lightly to avoid cutting into the wire.

If you accidentally nick the wire, cut off the damaged section and start over.

Common Mistakes To Avoid When Stripping Wire

Awareness of common pitfalls can help you achieve better results and prevent electrocution.

Neglecting To Check for Live Wires

Never assume a wire is not live. Always check and double-check it with a voltage tester before beginning any work.

Over-Stripping

Over-stripping occurs when you remove too much insulation, exposing excess bare wire, which can lead to short circuits or electrical shocks. Always measure and mark the correct stripping length before beginning.

Using Incorrect Tools

Using the wrong tool or incorrect wire stripper setting can damage the wire or create an unsafe connection. Always match your tool to the wire gauge and type you’re working with.

Professional Tips for Efficient Wire Stripping

Incorporate these expert tips to improve your wire stripping technique.

Measuring and Marking

• Aim for about 3/8 to 1/2 inch of exposed wire for most standard connections.
• For precision, mark the stripping point with a small piece of tape or a marker.
• Use a wire stripper with built-in measurement guides for consistent results.

Maintaining Your Tools

• Keep your wire strippers clean and free of debris.
• Regularly check the cutting edges for wear and replace when necessary.
• Store tools in a dry place to prevent rust and maintain their effectiveness.

Practicing Your Technique

• Experiment with different tools to find what works best for you.
• Practice on scrap wire to refine your stripping technique.
• Watch instructional videos for visual guidance.

Troubleshooting Wire Stripping Issues

Even experienced DIYers can encounter challenges when stripping wire. Here’s how to address common problems.

Dealing with Stubborn Insulation

If the insulation is difficult to remove, confirm that you’re using the correct size notch on your wire stripper. Before stripping, try scoring the insulation lightly with a utility knife.

Handling Brittle or Damaged Insulation

Brittle or damaged insulation can complicate stripping. First, try gently warming the insulation with a hair dryer to soften it. Then, use a pair of needle-nose pliers to pull the insulation away delicately.

If the damage is too extensive, consider completely replacing the wire.

Our Conclusion

Mastering the art of stripping electrical wire is a valuable skill for any homeowner or DIY enthusiast. With the right tools, techniques, and safety precautions, you can confidently tackle various electrical projects around your home.

Remember, while many electrical tasks are suitable for DIY, always prioritize safety. If you’re unsure about a project or dealing with complex electrical systems, don’t hesitate to consult or hire a licensed electrician.