WS159 water-soluble solder paste is said to consistently print in volumes down to 12 mm circles and meet IPC-7095 Class III resistance to voiding, using straight ramp and soak reflow profiles. Is reportedly fully cleanable. Is engineered to work with SnPb37, SnPb36Ag2 alloys with Type 3, 4 and 5 solder meshes. Works with OSP, ENIG, immersion silver, and immersion tin finishes. Results in bright, shiny SnPb solder joints, and solder spread on all common pad finishes. Features high-volume repeatability with 16 mm pitch QFP pads, and responds to one-hour pauses, after two knead strokes at 35 to 65% RH.
 
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