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Reply To: | TechNet E-Mail Forum. |
Date: | Wed, 5 May 2004 12:26:46 +0300 |
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Almost surely, this is due to a reaction between flux residues or
saponifier and metals (most probably copper, but could be nickel). It
would appear that either your wash/rinse process is not operating as it
ought or somebody forgot to put these boards through it.
Someone else here asked me yesterday why I considered the wash process
critical; this is an example of my answer! :-(
Brian
Charles Caswell wrote:
> I just got some pictures from a customer of what appears to be some green
> residue on some of the SMT leads. It is only on a couple of components on one
> assembly of five. We used a water soluble paste for the SMT, water soluble
> flux for hand solder and washed in a Westek inline cleaner with saponifier. I
> have seen the saponifier turn brass a blue/green color but not even close to
> this green. There are some connectors and one IC that do not go through the
> wash and are hand cleaned first with IPA and then a water rinse. Anybody got
> an idea? Maybe (please) I could get Steve to post a picture.
> Thanks in advance.
>
> Charles Caswell
> The Big Kahuna
>
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