Hi,

I recall that with stranded wire it is not a good idea to solder. Flux wicks
up into the wire and it just cannot be washed away. Most no clean fluxes are
type OA (correct me here) which is corrosive and needs to be cleaned. RMA is
better.

Solder also wicks up into the stranded wire making the wire very stiff. This
concentrates any flexing to the solder point which can fail. Crimping
stranded wire give some level of strain relief and this is why the soldering
of stranded wire in crimp terminals is not recommended. 

But, I am an old dog and my memory could be failing. Please let me know.

Bob K.

-----Original Message-----
From: TechNet <[log in to unmask]> On Behalf Of [log in to unmask]
Sent: Friday, March 8, 2024 1:19 PM
To: [log in to unmask]
Subject: Re: [TN] Metallurgical Inquiry

It is not recommended. I would first tin the terminals using RMA flux to
remove the gold. Tin the stranded wire with either RMA or no-clean and soak
in IPA, then blow off thoroughly and wash with a good saponifier, bake dry,
and then solder the tinned wires to the tinned terminals with the same
NC/RMA flux and clean again the same way. Do not use DI water first. Clean
off (or at least dilute) as much of the flux as you can with IPA, then clean
with water.
Otherwise you will have a reaction between the DI water and the no-clean/RMA
flux (white conductive residue).
Any flux residues that might remain after cleaning will be negligible.
Dean

-----Original Message-----
From: TechNet <[log in to unmask]> On Behalf Of Hernandez, Victor G
Sent: Friday, March 8, 2024 11:19 AM
To: [log in to unmask]
Subject: [TN] Metallurgical Inquiry

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Fellow TechNetters:

    Is it permissible to solder a stranded wire to a gold finger pads with
either Sn Pb or Pb-free solder?
Typically, gold fingers are electroplated, hard gold.
Any chance of galvanic corrosion?

Victor,




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