| Has there anyone bold enough to try this in their shops? My cubemate just got through telling me that at his last shop, they had bare copper boards (no HASL, no OSP, no nothing), with minimal solderability problems. | Is your cubemate the same guy who told me I could drive from Houston to New Orleans in three hours, 'cause he does it all the time? Or the one who says he shoots in the low 80's but can't par a hole to save his lif when you finally get out on the golf course? Smells like a little "embellishment" going on here.
I did have boards with a copper finish and no OSP. The only thing protecting the copper from oxidation was the Cu-chromate layer on the foil. These are the puppies that I frequently have referred to as the "bitch boards." The ones that only the Alpha 310B flux could solder. The ones used in our reduced purity nitrogen trials that caused defect to triple when the nitrogen feed in the wave was reduced from near 100% purity to 97% purity. The ones that exemplify that fine line between cost-effective and totally unusable (s)crap.
I guess it comes down to what you define as "minimal" solder problems. Then there's the school of thought that if you don't see the defect, and don't record the defect, then it's really not a defect, right? (No offense to your cubemate; I'm referring to a shop that I once worked in.)
So yeah, you can, under the right conditions, skip the protectant, but I think it would be highly unadvisable. If it were a realistic process, some big guys in highly competitive markets (like the Motorolas or Compaqs of the world) would be doing it and publishing papers about the great benefits of it.
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