Consider NOT getting involved in those little POS chunks of sheet metal. * They're expensive. * You never have the one you need. * Even if you DO have the item you need, you probably will not be able to locate it. * It's all but impossible to control paste deposition with them.
As an alternative, consider using tacky flux. Just: * Dip the BGA into a precisely leveled glob of tacky flux [Search the fine SMTnet Archives for an innovative approach to the precision leveling of tacky flux]. * Place the part. * Reflow the solder. * Live well, live long.
While you're perusing the fine SMTnet Archives, * Keep an eye out for a reference to a paper on BGA rework by Earl Moon that was published in the SMTnet Newsletter, circa maybe, maybe not late summer / fall 1999 or some other time. * Determine if reballing and reusing BGA is appropriate for you product end-use application. [The Archives may contain a reference to a Motorola position that they do not reuse BGA in shippable product, because of reduced reliability in BGA with multiple heat cycles.] * Recognize that following this suggestion of using tacky flux, in lieu of solder paste, would reduce the amount of solder that ends-up as solder attachments under your component. While this reduced amount of solder potentially lowers the reliability of your product, we have never found anything that supports this theory.
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