I need a good way to clean the oxides off copper electric wire. I run and splice wire outdoors and occasionally need to make new splices when lightning, animals or weather do bad things. It would be EZ if I could being it to my bench but it all has to be done in the middle of a field, maybe I can get an estension cord there. Is there some simple spray or dip that will strip the old oxides off so I can make a decent twist or solder splice? I don't have the luxury of cutting much off since most of the wire is underground.
You could try smearing a bit of soft solder flux (plumber's flux) on the bare copper and then heating it gently with a small blowtorch. Flux is usually pretty good at stripping away oxides.
My choice would be to use crimp splices with *good* crimp tooling. That will do a good job of displacing the oxide film and making a good connection.
Good crimp tools are made by AMP -- among others. That is the brand which I have collected over time, and there are even (relatively rare) tools which crimp both sides of a butt splice at the same time.
Since you don't want water running into the splice after it is done, I would suggest that you fill the splice (which is hollow all the way through) with silicone grease before pushing the wire into the splices.
I don't know what gauge wires you are working with, but a crimp splice with #22 Ga stranded wire takes something like 3/16" of strip length per end, and the splice usually adds 1/16" or more between the ends of the wire, so the total length loss will be very small, unless the wire has been badly mangled.
A dip in acid would remove the oxide -- but it would also wick up into the insulation -- and especially with stranded wire, and continue to eat at the wire until it produced an early failure.
I also, once -- *many* years ago -- had a box of field wire splices, which consisted of a hollow cylinder of solder, filled with rosin flux, and coated with some gray grainy compound which could be easily ignited with a match. This provided the heat needed to make the joint. But -- I got them from a surplus place back around 1954-1955 or so, and I have no idea whether such a product is still made. Even if you could find them, they would still require enough wire slack to twist them together.
eBay auction #4569868835 has a couple of crimpers which may be of use.
The one with the red handles is for red-insulated terminals from
22 to 16 ga wire.
The one with one blue handle and one green handle is for blue insulated terminals from 16 to 14 ga wire. (I have never seen the green terminals, though I presume that they existed at one time.
The one with yellow handles is not of much use unless you are dealing with quite small wires -- 28 to 26 ga IIRC.
I'm not sure what the other two crimpers in that "set" are. They look like those made by AMP -- but the designations given are not much help, and there are no close-ups.
You *do* need ones with yellow handles -- but larger ones, for the 12 to 12 ga wire. This one is in a different auction, but in Australia, and selling for way too much money at the moment. See auction # 7537833304 to see what they look like. The "16-14" ga I think requires terminals with thicker insulation.
Note that *all* of these tools are of the "P.I.D.G." style (Pre-Insulated Diamond Grip). The deform the terminal's insulation to grip the wire's insulation, so there is less flexing at the exit from the crimp terminal, and thus less chance of flex failures.
The pins on all of these are to change only the size of the crimp of the insulation -- not the wire crimp -- so you can get a proper grip on varying thicknesses of insulation.
Avoid the style of crimper shown in auction # 7538730835 It does not crimp the insulation at the same time, and does not have a ratchet to assure that the crimp cycle is completed before the tool is released. These are best considered "emergency use only" tools. There appear to be bins of the three most needed terminals in there -- red, blue, and yellow, including the butt splice ones.
Auction # 4569319248 appears to have a good one for the 16-14 ga range (blue/green handles). Often the colors have worn off of the outside of the handles, and sometimes they never were painted, for whatever reason. This one has a strange looking fixture for orienting the ring or spade extension of most terminals -- but this will have to be removed to use the butt splices anyway (a single allen screw to remove it. Be careful that the captive spring does not get lost, in case you need to use it for normal terminals later.)
Auction # 4569914565 has a later design, made to handle both the red and the blue terminals (total size range from 22 to 14 ga), and at the moment, the price looks nice. I've never had one of this style, however.
Any wire sizes beyond that go to hydraulic powered crimpers, and they are available from # 8 ga through 4/0 (or 4-0) gauge. The #8 through #2 use one size of hydraulic head with interchangeable dies, and the 1/0 through 4/0 use a second, larger, crimp head. (I have everything except the 4/0 dies by now.)
Note that I have had no dealings with any of the vendors represented in the auctions -- I'm just using the auctions to show you what to look for.
I've gotten some of my crimpers or crimp heads from eBay auctions, and others from hamfests or other surplus sales.
Except that there is sufficient acidity in that so it will eat away the wires over time. It is intended for such things as soldering plumbing -- not for wire soldering -- and especially not for stranded wire soldering.
For small wire, use emery cloth or sand paper. For larger wire or stranded wire, use a wire brush. They make a handle that holds 2 boar brushes in a V configuration, that we use in linework on large wire.
It still can wick up under the insulation during the soldering. This is why only rosin-based flux is used for electrical soldering
However -- if he is using sold rather than stranded wire (I've seen both used outdoors), my advice to use crimp splices and crimp tooling is perhaps not the best. The crimp tooling works better on stranded wire.
I'd try a CO2 bottle, regulator and Paasche "air eraser" or LAC#3.
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The latter is a gritblaster that looks like an air brush, shoots very fine but quite aggressive grit. It cleans copper bright about instantly, doesn't use much air (or CO2) in the process.
The wires are solid 12/2 with ground and most joints were just twisted together and wire nutted & taped. A lot of the ground wires were just twisted together & taped or not, and they especially have heavy oxides.
I want a CHEAP solution since I'm only doing a few at a time; yes it's solid wire and i'm not worried about the insulation since I can strip it back and only flux the bar4 wire.
I'm really fond of red scotchbrite pads. You can get the green (not quite as aggressive and a courser grain) at grocery stores, but various electrical supplies sell it as well.
After the splice is done, and since you're underground, cover it liberally with silicone sealant, RTV is better. Even better, use a waterproof underground splice. I've also used dielectric filled wire nuts meant for wet environments, and I've seen underground wire nuts in the hardware store but never had reason to use them. Is this underground cable that's getting dug up by animals or otherwise damaged? I'd highly recommend environmental splices rather than wire nuts. No slack used in the process. They are basically butt splices with a shrinkable sleeve over the top, and a sealing ring at each end. I use the AMP kind that requires special tooling and all that, but you'll see the ones I'm talking about in better suppliers. Slipping a piece of PVC or steel pipe over the repair beforehand provides some degree of protection since animals tend to dig up the same place over and over.
I've resisted posting this idea, due in part to it not being the best solution, but maybe it is. Sulfuric acid will not dissolve copper, but has an appetite for copper corrosion. You can boil copper objects in sulfuric acid with no ill effect, and end up with perfectly clean surfaces. Armed with that idea, maybe you could use a little sulfuric, maybe brush applied. It would be easy to wash off with water, so clean up wouldn't be a problem. Don't know how well it will work cold, though. And it's really tough on fabric and eyes.
What are you using this wire for? If it's for low voltage wiring like a 12/24V Malibu Lights system, you can use Rosin Flux (liquid or paste) before soldering, and not worry about wicking because it's non-reactive when cold.
If this is for 120V AC landscape lighting, you would be far better off with waterproof silicone grease filled wirenuts made for the purpose, King and Ideal make them, and they are carried at good Home Improvement stores and wholesale houses.
And for 120V wiring it does have to be enclosed in something - either a buried flush handhole (Christie, Et Al), PVC conduit risers and a PVC or Aluminum box, or a mounting post/bollard (RAB Mighty Post, Perma-Post, Arlington Gard-N-Post). Direct burial with no enclosure is not smart.
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