Lou
There is no reason why you should not clean sockets, provided you can
dry them effectively.
OTOH, I do NOT recommend you use saponifier with w/s chemistry. Why?
Saponifier is a combination of a strong organic or inorganic alkali with
some form of w/s solvent and is specifically meant for turning insoluble
cyclic carboxylic acids (e.g. rosin) into a soluble soap. You don't have
such acids in w/s chemistry. What it does mean is that your rinsing has
to get rid of this high-pH solution (generally >10) which adds to the
burden of the rinsing and contaminates your rinse water more than is
necessary. Also, the high-pH solution will be more agressive towards
amphoteric metals, notably aluminium and light alloys (electrolytic
caps, radiators etc.) amd may make your solder look slightly duller
(cosmetic). It also costs money. I suggest that, if pure water is not
good enough for you, you should use a chelating neutraliser or rinse aid
in your first stage (made by many of the flux manufacturers). This is a
much milder alkali (pH of the concentrate ~9), is cheaper, chelates the
heavy metals (which can actually precipitate in some saponifiers),
leaves beautifully brilliant joints. I very strongly recommend this type
of chemical with w/s chemistry and have had excellent results from many
clients. For thos using batch cleaning, it also has some other added
advantages and, for small-to-medium users, it can be used to avoid any
problems with waste water treatment (hold-tank technique). Have more
info if required (privately).
Hope this helps
Brian
Lou Hart wrote:
>
> TechNetters,
>
> Is it possible to clean assemblies containing socketed components in an
> aqueous cleaner? We have an in-line cleaner with 2% saponifier for
> cleaning after surface mount reflow (water-soluble paste) and after wave
> solder (water-soluble flux).
>
> My concern is with assemblies that have had components reworked with
> water-soluble flux after socketed parts have been installed. The cleaning
> procedure in IPC-7721, 2.2, recommends use of an automated cleaner, and
> provides instructions on hand-cleaning.
>
> Many thanks for any comments.
>
> Lou Hart
>
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