For those of you out there, like myself who are still using 2-d to measure paste ht, I have 2 questions. 1. Typically, what tolerance are you applying to your ht? +- 1 mil, or what? 2. Are you using metal squeegees, and if so, have you found that squeegees at 45 degrees will always add 1 to 1.5 mils of paste ht beyond your stencil thickness no matter what else you do?. Also - have you found that squeegees at 60 degrees will give you the stencil thickness in paste, plus perhaps only a half mil?
We are trying to tighten up our SPC a bit, and reduce some bridges, and I'm hearing a lot of stories, including many about the futility of 2-d measurements (which I understand) and how metal squeegees have basically taken out the impact that a lot of the other parameters, such as pressure, speed, etc, have had. I'm trying to help some "experts" get past the debate and onto the solutions. Somebody give me a sanity check. Thanx!!
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