Tin Immersion (Dexcoat FST) instead of HASL for SMT assembly.

We are currently investigating alternatives to HASL for circuit boards with 20 mil pitch smt pads and below. If you have experience with this product or simular immersion tin products with respect to manufacturing or assembly I am very interested in your opinion of its performance. Thanks

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| We are currently investigating alternatives to HASL for circuit boards with 20 mil pitch smt pads and below. If you have experience with this product or simular immersion tin products with respect to manufacturing or assembly I am very interested in your opinion of its performance. Thanks John, About a month ago my PCB supplier gave me a sample of a Tin immersion PCB (Dextracoat FST). On first glance, the surface looked ideal for fine pitch components - flat and even. I did a simple solderability test on it by printing solder paste on it, and sending it through a reflow oven with a profile used for HASL PCB�s. The solder did not bond properly to the surface. On most of the pads, the solder wicked to the one side of the pad. Needless to say, it did not pass my simple solderability test. Unfortunately, that is the only experience I had with Tin immersion. I don�t think it would be fair to make any conclusions based upon my experience with just one PCB. Maybe this specific supplied has not yet mastered the process. At this stage I am waiting for a reply from the PCB supplier. I would also like to hear more about Tin immersion from anyone else. Igmar Grewar Grinaker Electronics

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| We are currently investigating alternatives to HASL for circuit boards with 20 mil pitch smt pads and below. If you have experience with this product or simular immersion tin products with respect to manufacturing or assembly I am very interested in your opinion of its performance. Thanks

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| | We are currently investigating alternatives to HASL for circuit boards with 20 mil pitch smt pads and below. If you have experience with this product or simular immersion tin products with respect to manufacturing or assembly I am very interested in your opinion of its performance. Thanks Not a good idea. Tin oxidizes rapidly and excessively. Go to immersion gold over immersion nickel or palladium or silver or organic.

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