Tom,
I recommend .006" thick foil for stenciling on .50mm pitch parts.
Good luck,
Charlie B.




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 Subject: [TN] Screen for fine pitch parts






Good day Technet,
May I pose a question of screen thickness in regards to a surface mount
fine pitch part.  I have a surface mount PCA that is using a 100 pin, 20
mil.  spacing TQFP.   What is the ideal thickness of the screen I should
specify that is not going to put down too much solder paste, thereby
preventing bridging between pads?   Also, I have been reading a lot on this
forum about immersion white tin.   It sounds as though many of you feel
this is a good finish to use with fine pitch parts.   Normally I use gold
flash, but this sounds as good or better if the cost is not higher.   Where
can I find these archives at www.IPC.org so that I may review the
consensus?  I searched the site but could not find any link to archives.
Thank You,
Tom Burek
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