Soldering old, corroded copper wires (how to w/pics)

[Sodo]

I read of Ed's trouble soldering old corroded wires.
Everyone was on Eds balls for his soldering sklils, forgetting that Ed's just notafraidofit, unfazed even; by the Jack of all Tirades.
Ed will go at it, post pics, ask questions, learn skills, keep moving.
I like that.

I was in the middle of re-wiring my car-trailer, and since I was doing EXACTLY this, decided to post a how-to.
A trailer is a terrible environment for wires, it sits outside 24/7/365.
Mine were all corroded under the insulation.

=================================

Here's a way to solder corroded wires.

Here's what the wire looks like under the casing. Copper with this layer of corrosion is NOT solderable.

Fan the strands out.

Scrape lightly with a knife.
Flip the fan over and scrape thee other side.
Close up the fan and re-open it again at 90 degrees to expose the other sides of the wire.

If you keep scraping until the strands are completely clean it will solder very well.
But I've found good results scraping four sides (of each strand).

Theres another way.
If you mix vinegar and salt, and dip the wire into the mixture, it will take the corrosion off, leaving bright copper strands.
That kinda gives me the willies though, thinking of that vinegar+salt "wicking" up the wire and sitting in there for years.
I don't know if this is a genuine problem but have not heard either way.
You could try to neutralize it with baklng soda + water.
_________________


'90 Westy EJ25, 2Peloquins, 3knobs, pressure-oiled GT mainshaft, filtered, cooled gearbox
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered gearbox
....KTMs, GasGas, SPOT mtb

[rmcd]

Thanks for coaching Sodo and Ed sorry about your trampled wedding tackle. I too appreciate learning from your build thread.

I've been playing around with a product called DeoxIT D to clean and/or DeoxIT S to clean and coat. I also use diaelectric gel after cause I'm paranoid. No long term experience on the effectiveness of the DeoxIT S.
_________________
VW LT40 build. Like a Vanagon but 30% larger in every direction and 40% slower even in metric.
https://www.thesamba.com/vw/forum/viewtopic.php?t=749359&highlight=

[dhaavers]

Great suggestion on cleaning the oxidation before any soldering...essential, indeed!

FWIW, I 'd like to suggest the benefit of a proper inline splice for connecting
two wires. It will be much easier to waterproof with simple heatshrink -or- tape
and will be stronger structurally than the "pigtail" you've pictured.

Here's an excellent how-to showing basic "interlaced" splice:

http://www.instructables.com/id/Soldering-Tutorial-Inline-Splicing/

...and here's how Western Union and NASA do it for a more structurally sound splice:

http://www.instructables.com/id/Master-a-perfect-inline-wire-splice-everytime/
_________________
86 White Wolfsburg Westy Weekender
"The WonderVan"
<EDITED TO PROTECT INNOCENT PIXELS>

[Abscate]

That inline splice is neater and let's you heat shrink it without a big mess of wire pointing at 90 degrees to the wire run. You can then fit into a wire loom for secondary protection.


I learned that at NASA, too!
_________________
.ssS!

[greebly]

A NASA splice (inline lash splice) is linked below. I utilize 30 gauge bus wire to do the wrap. When done properly and sleeved it will not catch, chafe, and is the same diameter as the insulated wire. You want to leave 1 wire thickness on either end that the solder should not wick into, wicking can cause stiffness which can snap under flexing and vibration. The splice will be stronger than the original wire. https://workmanship.nasa.gov/lib/insp/2%20books/links/sections/graphics/407/407-09.gif

[Ahwahnee]

[greebly]

For some reason the NASA.gov website is not working, here is a picture of a decent joint. Notice that the depiction shows no solder intruding into the insulation, this is for flexibility to prevent failure under vibration. I use 30 gauge buss wire but you can strip some stranded wire back, isolate a strand and use it to wrap the splice.

[Gnarlodious]

I just sandpaper them, then use acid flux.
_________________
Vanagon ’83 diesel AAZ w/Giles injection, 5spd 4.57R&P+TBD and a '78 diesel Rabbit

[Abscate]

Daves comment on a solder joint being stiff is correct. Its best to strain relief a soldered joint by attaching it hard to something - on the starter circuit if you plan the joint in the right place you can zip tie it around the solenoid, with some chafe protection. A zip tie on each end of the splice is perfect.

NASA is the extreme for vibration, we don't have to worry about that quite as much on our VWs. My stuff paradoxically didn't get shot into space, it got dropped into the Earth, but it was still much worse than an auto application.
_________________
.ssS!

[MayorMcCheese]

Muriatic acid will clean those wire up really nice.

[Butcher]

I'm kinda confused. Why would there be a tutorial to solder a bad wire? Shouldn't it be more like convincing someone to NOT solder that wire, but to replace it?

I guess it's a skill that may be needed someday, but like your trailer, a rewire is warranted.

[Abscate]

Well, there is pretty broad spectrum of use. If old wire is functioning ok, economy can dictate getting good use out of it. Trailer lights are pretty forgiving with LEDs, the current draw is much less than they were probably designed for.

If I replaced every piece of old wire, I would be even more bankrupt than I am...if thats possible.
_________________
.ssS!

[Sodo]

Butcher most people need to choose their battles. I'm COUNTING on the LEDS saving grace, but the electric brakes,,,,I just had to splice to old wire as best I could. And its good. Sealed with liquid tape, strain relieved, immobilized.

And I like a NASA splice as much as any fella. Or to put it in the newly popular vernacular of our revered leader, "believe me, I like Inline splices bigly, I REALLY like a NASA splice ".

But lets say a guy with a 30yo van were to search "soldering corroded wires" because he needs to solve one or two few immediate problems thusly and bigly landing upon theSamba thread "Soldering old, corroded copper wires (how to w/pics)" ...... agreed this is a very seldom chance, but just in case.

Does anyone have any pics to add to the subject that are NOT perfectly clean wires spliced under perfect conditions? You could never do those pretty splices overhead near the starter solenoid on Eds van for example.

I can see how sandpaper might clen the wire too, but does the 'sand' contaminate the solder area, causing further soldering problems?

Re: Acids on your wires. As I wrote earlier I'm leery of using acids on a wire that can wick the acid inside the insulation and remain there, perhaps embrittling the wire where the flexible strands end. Is this a genuine concern?

There are lots of ways to splice wires, but what you do AFTER splicing, to prevent bending at the new "hard point" has a significant effect on the longevity of your repair. One layer of heatshrink tube doesn't support much, you still have to immobilize the splice. Some heat shrink tubes are lined inside with adhesive sealer, a nice feature.

But anyway, subject being "Soldering old, corroded copper wires (how to w/pics)" .... heres the solder part of the discussion, hope it helps some members to solve a problem.
_________________


'90 Westy EJ25, 2Peloquins, 3knobs, pressure-oiled GT mainshaft, filtered, cooled gearbox
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered gearbox
....KTMs, GasGas, SPOT mtb

[Terry Kay]

Link

_________________
T.K.

[greebly]

[Gnarlodious]

I can't hardly believe I'm the only person on this board that uses acid flux.
_________________
Vanagon ’83 diesel AAZ w/Giles injection, 5spd 4.57R&P+TBD and a '78 diesel Rabbit

[Sodo]

[Terry Kay]

Joining corroded, junk wires, isn't the way to go either.

If the wire is black where it was stripped, it's black under the rest of the insulation.
Acid bathing the ends of the intended area to be soldered is the correct way of approaching this solder joint.
It's the fastest way to get the wires clean anyway.

I sure don't know why replacing nasty old starter wire is a big deal.
Better than scabbing new ends on old corroded wires.
_________________
T.K.

[epowell]

Wow! Soldering is a popular topic! [even more than welding!]
...one good pigeon-poop solder pic from a fledgling newby and the whole forum is HOPPING

Thanks so much Sodo for this help! [and everyone else also!] This place is a Gold Mine full of wonderful, generous, and KNOWLEDGABLE Dudes!

You have to admit, this foto is priceless

_________________
www.edwardpowell.com

[E1]

Thanks Sodo and responders, great info!
_________________
‘84 Westy, 2.1L with Digijet, 5.43 R+P, GT Gears
"Adding power makes you faster on the straights.
Subtracting weight makes you faster everywhere."
— Colin Chapman