How to: Solder corroded copper wiring.

[mjc506]

So, how to solder corroded copper wiring. The sort you find around those sodding connectors behind the radiator <!-- s:angry-tappingfoot: --><!-- s:angry-tappingfoot: -->

If you've tried, you'll know that trying to apply solder to these wires just results in the solder beading off and not sticking, even with plenty of flux and high heat. You could use emery cloth to clean each individual strand, but there is a better way <!-- s:) --><!-- s:) -->

So, you strip the insulation from a cable, and find dark corroded copper underneath:

Don't try soldering it anyway (like I did) as you'll make the job harder.

You'll now need 5 ingredients:
Vinegar
Salt
Bicarbonate of soda
Water
Two small containers (glass, plastic... probably not metal)

In one pot, add some water to a reasonable level. Then add bicarbonate of soda (keep stirring) until it stops dissolving. The actual amount isn't critical, just make it as strong as possible. (This is your neutralising solution)


In the other, add vinegar to a reasonable level, then add salt. Again, the exact amount isn't fixed, just make a saturated solution. one-dissolved salt grains won't harm anything <!-- s:) --><!-- s:) -->


Now for the fun part.
Dip the bare corroded wiring into your salt/vinegar solution. Stir it around a bit. If you're lucky, you'll see some bubbles coming from the wires, but that's about as exciting as it gets... After a few minutes, the copper will be clean! (pouring half the vinegar over your boots appears to be an optional step...)


Now, if you leave these nice bright clean bits of copper exposed, they will sooner corrode from the salt in the solution. So now you should dunk them into your bicarbonate neutralising solution. Stir them around a bit to make sure all the vinegar/salt's gone.
(Shocking photo, I know <!-- s:shy: --><!-- s:shy: --> )

Clean wires! Dry them up, and solder! If the corrosion isn't gone yet (ie, you tried to solder before cleaning...) another few minutes should clear it up.


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[ProfG]

Or

just leave it in 7up or sprite for 30 minutes.

 

[mjc506]

Heh, coke works too, but it goes stick after haha

[Gassoon]

Nice oine , mjc !

You could use emery cloth to clean each individual strand...

been there years ago...

[iansoady]

It's also worth using proper flux on it when you've cleaned it - I have a tin of Fluxite paste (non-corrosive) that must be at least 10 years old.

[mjc506]

Yes, proper flux always helps, although my fluxed solder work fine after cleaning.

[mjc506]

Thanks, MartinW