On Mon, 22 Aug 2005, Marvin Dickens wrote: > I don't know. I've never bought it - although, I've made it. This type of > plate is really, really thin. As a comparison, a contractor grade garbage bag > is 3 mills in thickness. With immersion, your guaranteed 2 mills and possibly > 2.5 mills if the workflow is really good and there is no contamination. Rub on > plating gives only a few molecules of thickness. > > Both rub on and immersion are what is know as self limiting because as soon as > there is no exposed copper, the reaction stops. But, with immersion, the coat > is applied in an extremely uniform system under more ideal circumstances than > something being rubbed on (Immersion, like electroless and electroplating > yields a very uniform plate).
I think I'm convinced of your tin-silver immersion plating. A few more questions, if you don't mind: Once you mix up a liter of this stuff, how long can you keep it before it goes bad? How many times can you dip circuit boards in it before the solution is exhausted? I think I can borrow a chemistry lab to make this stuff. -- David Griffith [EMAIL PROTECTED]
