I resemble that remark.
Earl Grey Great Tea
----- Original Message -----
From: Ingemar Hernefjord (EMW) <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, October 05, 1999 9:52 AM
Subject: Re: [TN] Cold solder
> Earl Grey is a good tea, I agree,
> Now, Joan, are you sure it's about cold soldering at all? As you describe
it could as well be dewetting. If it's dewetting, your trouble shooting can
leave the wavesolder for a while. Again, I wonder why you don't do a wetting
test on the terminals.
> Good Lunch
> Ingemar Hernefjord
> Ericsson Microwave Systems
>
> ----------------------------------------------------------------------
> Earl and all,
>
> the soldering was a lot better before. We've always had the QA on our
back,
> checking the flux density and the settings for the problem assemblies.
> Myself, I don't recall having seen so much cold solder.
>
> The machine had been calibrated last saturday during the monthly
> maintenance, when the pot is thoroughly cleaned.
>
> It's possible that the solder mask changed, since it's darker now.
Together
> with the soldering problems we started experiencing discoloration of the
> solder mask on the solder side. But wouldn't this randomly affect any
place
> on the surface? I still get the connectors OK, with bad solder joints on
the
> caps and resistor networks.
>
> There has been no artwork change. However, could some changes in the
> materials or manufacturing of the board affect somehow the thermal mass
here
> and there? I mean, maybe the connectors drain somehow the heat from the
> adjoining components.
>
> And anyway, what on earth generates cold solder in the waving process?
>
> Ioan
>
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