Stripping exterior underground Romex
I had to do a little work over the weekend with that UV resistant outdoor underground type Romex. It’s the kind where the gray outer material fills in completely between the three wires. Stripping the outer jacket took a lot of slow, careful carving with a utility knife. It’s the kind of thing I’m sure somebody here must have a better way to do. Any suggestions?
Thanks —
— J.S.
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Romex stripper?
Worth a try, though it doesn't look like it gets the part between the wires. Thanks.
-- J.S.
Be real careful working with those. New they seem to work pretty well if care is taken and the NM is cooperative. Some brands of NM don't work as well with that sort of tool.As the tool gets older and duller the tendency is to jerk or twist the tool sideways. This tends to damage the insulation. In extreme cases it can nick or sever the conductor. The small crosswise slits are easy to miss as they are very close to the square cut of the jacket. I once had a journeyman swear up and down his tool, his made by Ideal, wouldn't do any damage. I set him up with some lengths of NM that had been sitting on the suppliers shelf for a time. Typical of a lot of the cable we get and old work situation. Told him to strip the jacket off both ends of four or five lengths. Then we took the cables into the sunlight and examined them closely. Two of the cable ends had damaged insulation. One had a crosswise slice into the insulation on the neutral and one had cuts in the installation around both the hot and neutral. The exposed copper was within a fraction of contacting the bare ground. He protested it didnt make any difference. I didn't see it that way. I don't allow them to be used on my jobs. IMHO it is far too easy to cause damage that may not show up for decades. Until some future time comes when they can reliably be shown to not cause insulation damage when used quickly by bored and tired tradesmen I won't be using them on my jobs. As I pointer out to "Inventor", what ever happened to that thread, there are all sorts of new inventions and methods that come out. Many have something going for them. Most don't make it long term.They are, IMO, no faster than a trained electrician with a good sharp knife. Especially if the tool user has to stop and look closely for insulation damage hidden by the jacket. Something that requires time and a strong flashlight to do effectively on most boxes.Another down side if working inside a box is that it is much more difficult to strip off the jacket with such a tool if working inside a box. The orientation of the tool to the cable is critical. More than once I have had well intentioned workers come to me with wires badly mangled because they got the cable in sideways. A nicked conductor is a likely point of failure. Even if everything lines up the nose of the tool makes it difficult not to leave several inches of jacket inside the box. Simply sloppy but less an electrical hazard. Repeated for two or three cable it can make dressing and stuffing the box much more difficult.Generally I can spend ten minutes with someone and have them stripping jackets faster, more effectively under a wider set of situations than using such a specialized tool. Generally I have noticed these tools tend to get used a bit and then, more and more, left behind. Most slowly rusting away in the bottom of a tool box or pensioned off on less experienced tradesmen.
I'm a knife guy myself.
Re: "I'm a knife guy myself"I didn't mean to seem like I was coming down on anyone. I too like to see what is new and try them out. Nothing here today can't be improved. The tool highlighted is an interesting concept. I had to give it a try. I was lucky enough to have several close enough to borrow. At first I was impressed. Only later, as I looked more closely, were the problems made clear. Oh well it was worth a shot. All part of the process. I'm sure it took a lot of bashing rocks together to get the first usable stone edge made by man. Most experienced electricians I know tend to concentrate on simple but highly adaptable tools. Especially if they work out of a tool belt where real estate is precious and weight a constant issue.
I'm a old Kentucky boy, always have a knife on me. Cut just a bit through the insulation, bend till something shows, cut some more if necessary. No nicks allowed.
Re: ..."always have a knife on me."Used to be most men wouldn't leave home without a knife, of some sort even if it was just a pen knife, in their pocket. When did this change? Why?Given my druthers I wouldn't ever be without a knife, a source of fire, a bandanna (handkerchief in more formal settings)and a bit of light line. Never know when you might want to tie something, or someone, up. No need to carry a Rambo sized blade. I knew a guy who used to hunt in Africa and he noted that they skin elephants with knives with blades seldom longer than a couple of inches long. I know I shouldn't but I often feel something like pity for a guy who can't produce a sharp edge of some sort. Even if it is nothing but a pen knife with a 1" blade. It is said some cultures, such as the Sikhs, carry a ceremonial blade as symbol of manhood. IMHO they have a point.
I am known for the sharpest edges too. Several people want me to sharpen their knife now and then. I would show them how, but then they would know how easy it is. Assuming it is just dull, a few swipes over the diamond hones, then buff with the rubber strop with green compound. Hold the knife in bright light to see if you can get any reflection off the edge, if so you're not done yet. The edge looks polished with no burr and no reflection under bright light. Yeah they are shaving sharp, and hold an edge pretty long.
I quess it's the red neck in me. If someone ask "do you have a knife" I say "do I have my pants on"
I always carry a small pocket knife. The same one for many of years! Comes in handy.
Times have changed for the worse here. Wore a sheath knife for many years on all occasions. Pants on, knife on. Liked the 4" Kershaws. Then folders - which don't interfer with my bags, then those folding razor knives with a Leatherman on the off side.
But - try to get our laborers to even carry a knife. Repeatedly:
"Cut this."
"I don't have a knife."
(Your're male, over 21 and you are not wearing a knife?!) Afraid American youth are being Made PC and tame. Can't carry a knife to school anymore. Etc., etc.
The ToolBear
"Never met a man who couldn't teach me something." Anon.
Sounds like UF, Underground Feeder, cable. Description in Article 340 in the 2005 and 2002 NEC.
UF, when relatively new and still soft, isn't too much of a problem. As it ages the outer jacket goes from softish rubber to the consistency of old leather. Worse still is that it becomes almost exactly the same density and toughness of the insulation on the wires. A sharp knife which would naturally be guided by feeling the differences in density has to be worked entirely by sight. In the worse case essentially whittling a set of insulated wires a PITA but not one without some technique that can make it a little easier.
New UF cable is easier. A good sharp knife, I usually use a fixed-blade box cutter, run down the center of the flat the length of the wires I want to end up with. Look closely at the cross-section of the cable. Usually the jacket over the ground wire is thinner on one side. Pays to slit this side. Why work harder than you have to. Slitting the center of the jacket frees up the ground wire even if you don't cut all the way down to it.
Just grab the exposed tip of the ground with Kleins and rip down. On really fresh UF you can sometimes just grab the tip of the ground and rip down. Sometimes it takes a small slit to allow the ground wire to get a start. On new UF you could rip down the length of a roll if you had to.
Once you get to that stage it pays to again look closely at the cross-section of the cable. The amount of tough grey jacket is thickest to the outside of the cable. With the ground gone you have a heavy husk with both the insulated conductors still encased. But there is a weak point. The plastic which was between the insulated conductors and the ground is quite thin. A fraction of the thickness of the outer shell.
Usually you will need to make a small slit beside each insulated conductor through this thin section so the wires don't try to split through the tougher outer side. Just an inch or so of slice is enough. Then, as with the ground it is a matter of grabbing the tip of the wire and ripping it down and out of the jacket.
That's the general plan. It works well for new or moderately aged UF cable. As the cable gets older and tougher you do less smooth and easy ripping and have to use more force. Two pairs of pliers, a strong grip and arms helps. Also more cutting is needed to get the wires out.
Sometimes, especially in cold weather, heating up the UF jacket helps on the worse cases. A propane torch can be put to good use. Prep the tip in the normal way with slits and exposed wire tips. On the really hardened jackets I blast it strongly. The outer jacket gets well browned and soft which allows you to pull first the ground and then the other two through the softened jacket. But you have to work fast.
You just want to soften the jacket not melt it so some practice and feel for it is required. I sometimes try to save lengths of the oldest, toughest UF I have dug out so the helpers have something to practice on. I start them on brand new UF and then, once they are adept at the technique, I whip out some ancient stuff on them. Always good for a laugh as the shine comes off their new found mastery of UF cable. Some seem to never get the hang of working the torch into the equation.
Thanks, I knew you'd come through on this one. I'll have to try the torch technique, and your sequence of operations.
This stuff has been buried about 10 - 15 years. It worked the way the P.O. had it wired, but now that I've put a GFCI ahead of it, I'm having to replace the parts that have been nicked by gardening tools. The new installation will be PVC conduit, so that kind of ground fault shouldn't be a problem any more.
-- J.S.