Issue link: https://iconnect007.uberflip.com/i/935136
FEBRUARY 2018 I SMT007 MAGAZINE 73 issues mirrored Crow's, but she had already found the missing ingre- dient that he was look- ing for, a nanocoat- ing. Shea's research had led her to advocate Aculon's NanoClear, a stencil treatment tech- nology, for several years as she had been able to demonstrate significant improvements in perfor- mance across many SMT lines. When Crow added NanoClear to his SMT process, he followed Shea's advice and expected to double under-stencil wipe cleaning every fourth or fifth board to every eighth or ninth or t e n t h b o a r d . W i t h Aculon's NanoClear, Crow's throughput was increased by a third and the factory's defect as tracked by Koh Young Zenith and AOI dropped by 52%. All his projec- tions were blown away. Crow's line could now run 24 print cycles before cleaning. Their AOI and ATE tests saw no reduc- tion in quality. With a faster screen printer, a faster SMT line and a cleaner process, Crow maintained improved quality while running faster. The Numbers Crow thought he had found the trifecta— softer wiper paper, engineered solvents and a nanocoating. As a result, Crow deliv- ered terrific results for Rauland: SMT- related defects were reduced by over 50%; throughput was increased by over 20%, and the company saved $1 million per year for three SMT lines. First pass yield went from 80% to 99%. The line had a 79% reduc- tion in under-stencil wiping as the interval went from five prints per wipe to 24 prints per wipe. Using the downloadable cost of ownership calculator Shea created for Aculon, Crow could Figure 2: With the cost calculator, management could easily see the result of the process improvement program. Figure 3: The cost calculator considers the costs of rework, both simple and complex, the cost of wiper paper, and the cost of the solvent.