How to Strip Wire Jacket from NMD90 (Residential Wire)

Written: May 6, 2022

Updated: Nov 14, 2022

Posted By: Riley Weller|Roughing-In

How to Strip Wire Jacket for Electricians (Residential NMD90 Wire)

Affiliate Disclaimer

Some links contain affiliate links which means I may receive commission if you click a link and purchase a product. These are all my own opinions - money will not sway me!

In this article I will discuss how to strip the jacket off of NMD90 wire.

This article is part of a cutting in series, so make sure to read the other articles!

(Cutting in is a term electricians use in the rough-in stage where they prepare their wires by removing the insulation jacket, entering the wires into an electrical box, and stripping conductor insulation to prepare for splicing).

How to Strip Wire Jacket off NMD90 with My Favorite Electrical Knife.

What We Cover in this Article:

Ways to Strip Wire Jacket off NMD90 Electrical Wire

Ways to Remove NMD90 Wire Jacket

How electrical cables work is there is an outer jacket, also known as the “sheath”. We remove this, which exposes the conductors. (Sometimes wires have additional layers of protection, such as a “jacket”, then “armor”, then sometimes paper, and even sometimes ANOTHER jacket underneath it all.. then FINALLY the conductors).

But, we’re talking about NMD90 14/2.. typical residential home wire, and it just has a white jacket, and it has a black, white, and bond conductor waiting inside for us! ⚡

nmd90-jacket-sheath-stripped-removed — NMD90 14/2 Wire (Typical Residential Copper Wiring).. We electricians remove the white jacket “outer sheath”, and expose the conductors to move onto the next step (which is using wire strippers to remove the insulation off the conductors, and then splicing wires to continue on the circuit!).

I won’t be covering removing AC90 (armored cable) sheathing in this article, only how to strip NMD90 14/2 wire (the most common wire for residential homes).

READ: Residential Wire vs. Commercial Wire

(I’ll also show you a cool picture and video below of “skinning the jacket” with a pocket knife, which an awesome journeyman taught me one time!)

Using an Exacto Knife (Snap Knife) to Remove Insulation Jacket:

To remove this jacket, we electricians use a knife, and each electrician has their own favorite knife.. (it’s not something you’re going to win in an argument.. 🤣)

My favorite way of removing this outer jacket is using a snap knife!

I’ve seen electricians use pocket knives, hook knives, or utility knives..

Step-by-Step Pictures of Stripping NMD90 Jacket:

strip-wire-jacket-2-finger-wire-guide — My left hand holds and pulls the wire.. my right hand holds the knife and SCORES the jacket. (Notice my two fingers are under the wire to guide the wire to keep the knife in the groove for control).

strip-wire-jacket-score-sheathing — The key word here is SCORING the jacket.. so don’t dig into the jacket, otherwise you can damage the wires inside! (Most electricians do dig in, and it’s okay to do it, but this scoring technique I’m sharing is a FULLPROOF way to never screwup!)

cut-deep-into-NMD90-jacket-for-a-handle — Near the last 3-4 inches of the wire you can cut in deeper to create a handle to pull off the jacket and expose the conductors inside!

grab-the-handle-from-deep-cut-nmd90-wire — You can see this creates an easy handle for you to pull! (Again, if you make this too short, it will be hard on your hands.. at least 3-4 inches, and you’ll be laughing! 😂)

nmd90-pull-off-scored-jacket-uncompromised-wires — You can see me in MID-ACTION pulling off the NMD90 jacket (sheath) to expose the black, white, and bond wire! (If done right, it removes REALLY easily!)

nmd90-cut-off-excess-jacket — The final step is to cut off the jacket. Now, as an electrician, you want to take pride in your work.. so make sure it looks clean, but DO NOT RISK cutting the wires. It’s more important that the wires are not damaged than “being perfect”. At the end of the day, the wires go into a box and no one sees it, to be real.. Just don’t have TONS of excess 😎

And that’s it!

I use my favorite knife, gently score the jacket, then cut in a little deeper near the end of the jacket. I then pull the jacket back up the wire, and I KNOW the wires have not been damaged.

I then simply remove the excess jacket, and the next step would be to stick the wires into a box!

What is this “Wire Skinning” You Speak Of?

So first, I didn’t invent this.. it was shown to me!

how-to-skin-nmd90-with-a-pocket-knife — Skinning the Jacket off NMD90 with a dull pocket knife! (See below for video!)

If you’d like to see the full video of this wire skinning, check my video on the Best Knives for Electricians.

But, I did upload a little snippet to save you some time just below:

Stripping NMD90 Jacket with a Pocket Knife

Here’s how the wire skinning works..

You have to use a really dull pocket knife. You simply SKIN the jacket off the NMD90, which allows for a really fast workflow.. I got pretty good at this, and over time and was even able to strip two wires at once!

I don’t think I ever skinned too deep and nicked the wire.. so it was a pretty solid and safe approach because the pocket knife is so dull 👍!

Conclusion.. Stripping NMD90 Wire Jacket

Alright, so make sure to read the other cutting-in articles..

You will learn:

How to strip single conductors to expose the copper
How to splice multiple wires for an awesome splice EVERY TIME!

Hope you have enjoyed the article and the website! 🙂

As always.. go for a laugh with some electrician jokes!

Free Electrician Training

splice-wire-at-the-insulation-to-being-braid

Riley Weller

In 2008, Riley became an electrical apprentice in Canada who completed his Red Seal 2016! He had the honor of working with many seasoned journeymen who passed down their tricks to him. Fun Fact: Riley is now a fulltime beatmaking educator!