In a message dated 06/07/2000 6:29:18 PM Central Daylight Time,
[log in to unmask] writes:

> Hello:
>
>  Our customer made a mistake on their print.  Instead of specifying
>  immersion gold, they specified Hot Air Solder Levelled.  Now they have
>  LOADED boards that they want to get immersion gold on.
>
>  Has anyone done this?  The questions I have off the top of my head are:
>  1. How do you protect the components from the immersion gold?  Would
>  conformal coat work?
>  2. Do you have to strip the solder first, or can you go gold over
>  solder?
>  3. What, if anything, would all this do to reliability?
>
>  Thanks for your help....
>
>  ralph richart

Hi Ralph!

I've got say, I can't think of any good reason why in the world your customer
would want to put immersion gold on a board that has already been built.
Immersion gold is normally just to make us assemblers lives easier...you have
nice flat pads to print solderpaste on fine pitch, unlike the domes you get
from hasl...and that's the ONLY reason that I can think of to use immersion
gold, nothing else.

If the boards are already built and they work, leave them alone...

-Steve Gregory-

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