Hi Luis,

My understanding of OSP is that it is designed for use in a two sided SMT
process.  With bare copper, when it goes through the first reflow (with
components and paste on the other side) it will oxidize.

The purpose of OSP is to protect the copper during the first pass and burn
off in time for the second pass.

I don't understand your question with regards to water.  Your board should
not be exposed to any water until the assembly process has completed (both
sides and wave solder) and you are washing the board.

myke
>>>>>I believe Luis means "varnish."
>
>Sure !. Sorry for the spelling. %-/
>
>So seems that the solderable V-arnish is only manufactured in spray can :(
>Would prefer to use it liquid.
>
>More questions about PCB potting/water-resistant/water-proofing:
>
>My PCB manufacturer just sent me a letter telling that he can actually use
>"OSP" technology in PCBs. OSP stands for "Organic Solderability Preservatives".
>
>Does anybody knows if this OSP technology can be used to provide good water
>tolerance (not to inmersion but splash) being solderable at the same time ??
>
>Then would be similar to apply solderable barnish spray.
>
>

"I was well aware that the processes of puberty are often fatal to psychic
power."
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