Terminating Tip for Corroded Wire

[Wotname]

Originally Posted by rwidman

I suggest re-reading the thread and considering one of the alternative fixes. There are better ways to accomplish what was done.

Please just remind me what you consider to be the best alternative quoted so far?

[Wotname]

Originally Posted by Aaarrgh

Quoted, "In this instance, this was not an option (at this time), it had to be terminated and it had to be perfectly serviceable for the next couple of weeks / months."

Since this particular circuit is not identified by the author of this thread, we must assume that this level of urgency must have been due to the circuit being responsible for supplying power to the BEER COOLER! Aarrrgh!

Fair call .

In fact, circuit purpose deliberately not specified due to customer confidentially and possible big $$ involved.

Regardless, electricity follows the same rules no matter the purpose of the circuit

[rwidman]

Originally Posted by Wotname

Please just remind me what you consider to be the best alternative quoted so far?

1) Go back along the wire to where the wire isn't corroded, splice on a new piece of wire, then terminate as usual.

2) Mechanically (scrape) the individual strands, then crimp as usual. A follow up with electrical contact cleaner before crimping wouldn't hurt.

[Wotname]

Originally Posted by rwidman

1) Go back along the wire to where the wire isn't corroded, splice on a new piece of wire, then terminate as usual.

I cut back about 1' and still black, no more to cut back and a splice further back just wasn't possible. I agree that would have been a better fix but not possible at the time.

2) Mechanically (scrape) the individual strands, then crimp as usual. A follow up with electrical contact cleaner before crimping wouldn't hurt.

Scraping 48 strands each 0.2mm diameter wasn't going to happen. As for contact cleaner, yes, I should have used the Deoxit I had in my bag - as previously posted, just forget

I did consider crimping but given the state of the wire I wasn't certain that the fix would last for the few weeks needed. I knew if the wire soldered properly (and it did), the electrical aspects were certain to be good. The soldered fitting could be mechanically secured in this instance.

The point of the thread is that a 20% solution phosphoric acid proved to be a suitable corrosion remover / cleaner of copper wire. It isn't about best practice, rather what might work when the job just has to be completed in the field and one is out of best practice options.

[Jim Cate]

All of this rhetoric has gotten me wondering...

The black oxide coating referenced is IME very very thin. It does seem to be at least somewhat conductive, though doubtless less so than pure copper. It will prevent decent solder connections being made. Wottie's method removes the oxide to allow good soldering. The black oxide, no matter how far up the wire in extent, does not remove a significant amount of the cross sectional area of the strands, thus the ohms/foot value does not change much at all for the length of the wire.

Thus, it seems to me that his repair, while not the elusive "best practice" which folks like to trumpet about, is indeed serviceable. It might have been better to neutralize the phosphoric with a warm bicarbonate of soda dip, but just rinsing will likely be fairly effective.

All of the insistence on tinned wire in pristine condition being the only acceptable practice seems to ignore the thousands of European boats being built with untinned wire. Their lights seem to work ok, even if their steering fails...

The other common corrosion seen on wiring, the green stuff that accompanies salt water immersion plus electrical power, is a different matter entirely. It removes very significant amounts of the cross section - sometimes ALL of it - and is totally unacceptable.

Jim

[01kiwijohn]

It got you home?? Ok then, excellent job!

[mcgann454]

Here is a trick I read a while ago and it works very well.
Quote from the net.
How to clean copper wires that have corroded black
I found this, tried it and it works.

How to perfectly clean wires in minutes!!!

Here is an old ham radio operators trick for cleaning wires for soldering that are old and corroded. It is hard to find this technique printed anywhere! I am a ham, NH7ZE, and learned it from my elmer (mentor). I am passing it on. I hope it helps people who need to clean wires:P Please vote!!!

Normally, if you strip a wire, and see it is corroded, there is not much you can do to restore it's shiny new conductive properties. There is scraping and scratching which comes to mind, but you'll never get it to the solderable slickness it once was long ago. After laboring and fretting over the corroded pieces of wire for a long, long time, you see that your sweat coming out of your palms and fingers are corroding the copper AGAIN!!!! Oh, dear. NOT TO WORRY!!!!! Give yourself a pat on the back, because what you will pull out of your bag of tricks now, will send all the corroded copper wires scurrying and scampering away in fear!!!! Here is how to clean any corroded wire without even touching it, in 30 seconds!! And what's more, you can even solder it!!!

This process uses two solutions, one is regular table salt and vinegar. Any kind of vinegar will work, from balsamic, to rice, to white vinegars. Its the acidity and corrosiveness of the salt and vinegar together that you want. The other solution is Sodium Bicarbonate, or baking soda, and water. This is used to neutralize the corrosive properties of the other solution, and to further clean the wires.

Step 1: Strip the wires to be cleaned.

Step 2: Get 2 containers, one for each solution. They can be paper cups, plastic, glass, bowls, whatever you can find. I have vials, because I am a professional electronics installer and I use these solutions out in the field.

Step 3: Get 1 tablespoon of raw salt, and put it in one of the containers. Fill up the rest of the container with vinegar, and stir the both together. As a general rule of thumb, put as much salt in the vinegar as will dissolve.

Step 4: Get 1 tablespoon of Sodium Bicarbonate, (baking soda) and add it to the other container. Fill up the rest with water, and stir well. Add more baking soda to make it cloudy. The amount is not important, as long as it is alkaline to cancel the acid of the vinegar solution.

Step 5: Put the stripped end of the wire in the vinegar solution, and stir the solution with the wire. any wire you want cleaned needs to be under the solution. Movement of the wire in the liquid speeds up the process.

Step 6: After 2 minutes or so, the wire will look very shiny and new in the vinegar solution. The acid and salt in the solution is etching away the oxides, exposing the bare metal. Make sure the metal is uniformly shiny. Leave it in longer if it is not perfectly clean throughout.

Step 7: Once the wire is satisfactorily clean, remove the wire from the vinegar, and plunge it into the baking soda solution to neutralize the acid's corrosive properties. If the wire was exposed to the air, without neutralizing the acid first, it would quickly corrode again. The baking soda keeps it clean and shiny. Swish the wire around in the baking soda water for about 10 seconds, and then you are done!! Shiny new wire ready for soldering, and conducting once again!!

[Wotname]

Originally Posted by Jim Cate

All of this rhetoric has gotten me wondering...

The black oxide coating referenced is IME very very thin. It does seem to be at least somewhat conductive, though doubtless less so than pure copper. It will prevent decent solder connections being made. Wottie's method removes the oxide to allow good soldering. The black oxide, no matter how far up the wire in extent, does not remove a significant amount of the cross sectional area of the strands, thus the ohms/foot value does not change much at all for the length of the wire.
…………..

Well, while we in the speculative mode, remember the diodes used between the vacuum tube era and the semiconductor age; they were metal oxides deposited onto a pure metal IIRC.

I well remember having a generator on a english car (positive earth) and it would not charge but it would start perfectly well. Turned out to very thin oxide on one of the battery posts (I forget which one). It didn't look corroded and it was tight, but after a week of searching for the fault, the terminals were cleaned and all was good again.

So I wonder about black stuff on copper wire...

[Jim Cate]

Originally Posted by Wotname

Well, while we in the speculative mode, remember the diodes used between the vacuum tube era and the semiconductor age; they were metal oxides deposited onto a pure metal IIRC.

I well remember having a generator on a english car (positive earth) and it would not charge but it would start perfectly well. Turned out to very thin oxide on one of the battery posts (I forget which one). It didn't look corroded and it was tight, but after a week of searching for the fault, the terminals were cleaned and all was good again.

So I wonder about black stuff on copper wire...

Geoff, maybe we can do some simple measurements of the R of the black layer. We are heading towards Port Huon tomorrow (Tuesday), so if you have any remnants of the offending wire, save them and we can play science!

And maybe have a glass of red to stimulate the process!

Jim

PS The English car episode means nothing, nothing I say, for it was undoubtedly produced by the Prince of Darkness, so of course it wouldn't charge...

[tankersteve]

Heh, the sanctimonius attitude of some on this thread are just, well... bless their little hearts.

Thank you to the OP for the great ideas on how to make some expedient repairs and restore a wire end to make a decent connection again. I can certainly see where this would be helpful when time and location are problematic, or even when troubleshooting, before replacing some wire with the 'optimal methods'.

Perhaps mods should delete some posters' accounts, less a newbie think all sailors are all-knowing jerks who can't derive the original intent of a thread.

Tankersteve

[Cadence]

Originally Posted by Paul Elliott

The OP wasn't "hack advice". Sometimes you have to do what you have to do, and that was a reasonable technique to use for a temporary / emergency repair.

I've had to fix corroded wiring, where the strands are black no matter how far you strip the insulation back. Yes, they should have used different wire, and if I had the time, materials, and opportunity I would have replaced the entire wire run. But I didn't, so I used sandpaper to expose the clean copper and I crimped a new connector (or an extension wire with a fresh connector). If I had phosphoric acid I might have used that. I will do whatever it takes to get home.

I believe he even stated it was a temp. fit. So you so right.

[Aaarrgh]

Solution #46 >>> Please refer to Solution #22, compare to Solution #17, integrate with Solution #31, and finalize with Solution # Rum Punch Aaarrgh!

[Cadence]

Originally Posted by Emmalina

Here's a tip that I use occasionaly soak overnight in Coca cola. More available than acids and strange as it may sound it works....

And drop a tooth into a glass of Coke. It won't be there in the morning.

[Paul Elliott]

Originally Posted by Cadence

And drop a tooth into a glass of Coke. It won't be there in the morning.

Urban legend, and false, accouding to Snopes: Coca-Cola Dissolves Teeth : snopes.com

Too bad they didn't test copper wire!

[Cadence]

Originally Posted by Paul Elliott

Urban legend, and false, accouding to Snopes: Coca-Cola Dissolves Teeth : snopes.com

Too bad they didn't test copper wire!

All I can base that on, is a neighbor telling me that she observed that will in college for her RN BS at the time. Now the formula of Coke may have changed. She is 78 now. And snopes is questionable as far as the source of funding? JMHO

Regardless, It may take awhile to rot out kids teeth. I believe the post about the wire and Coke was a good indicator.

I have no dog in the hunt so readers can take it or leave it.