I read with interest in September Circuits Assembly magazine an article entitled "Reducing Variation Through 'Intelligent' Stencils. In this the authors propose that by REDUCING stencil thickness from 0.005" to 0.004", the paste deposit volume will INCREASE by 76%. The test aperture was a 0.010" circle. Their argument,(which I don't doubt), is that by reducing stencil thickness the transfer efficiency is increased by increasing the aspect ratio. In a nutshell - the thicker the stencil the more paste stays in the aperture, the thinner the stencil the more paste goes on the board. This would seem to make sense to me, particularly when you get down to 0.005 - 4 stencils. I very rarely use circular apertures and would be interested in any feedback from "mounties" in production facilities. Anyone tested it? What were the results etc. Cheers, Darby.
P.S. Chicago was spectacular Dave.
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