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| Reply To: | TechNet E-Mail Forum. |
| Date: | Thu, 5 Jul 2001 11:14:33 -0500 |
| Content-Type: | multipart/mixed |
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Problems I have seen with pre-washing prior to assembly are when the cleaning process is not monitored and you end up with more contaminates then what was there to begin with. Or even handling issues from adding more touching of the product.
Over the years and all of the tests I have performed I have found very few lots that came from a PCB shop that didn't meet IPC-J-STD cleanliness requirements. The only exception was a supplier that did not understand the cleanliness requirements.
Why not sample test on receiving and enforcing a cleanliness spec to the PCB supplier? Do you also pre-bake the PCB's prior to use? What enviromental controls do you have to prevent further deterioration? What do the line operators do with these nice clean boards? Do they use gloves, edge handling only, etc?
Kathy
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<DIV>Problems I have seen with pre-washing prior to assembly are when the
cleaning process is not monitored and you end up with more contaminates then
what was there to begin with. Or even handling issues from adding more
touching of the product. </DIV>
<DIV> </DIV>
<DIV>Over the years and all of the tests I have performed I have found very few
lots that came from a PCB shop that didn't meet IPC-J-STD cleanliness
requirements. The only exception was a supplier that did not understand
the cleanliness requirements. </DIV>
<DIV> </DIV>
<DIV>Why not sample test on receiving and enforcing a cleanliness spec to the
PCB supplier? Do you also pre-bake the PCB's prior to use? What
enviromental controls do you have to prevent further deterioration? What
do the line operators do with these nice clean boards? Do they use gloves,
edge handling only, etc? </DIV>
<DIV> </DIV>
<DIV>Kathy </DIV></BODY></HTML>
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