Electronics Forum | Thu Apr 13 04:50:53 EDT 2006 | Slaine
I had something similar a while back it looked like fibreglass insulation in my case (was using no clean flux not water based), i took some and melted it with a soldering iron and it reacted like flux. and i tried disolving it with acetone.
Electronics Forum | Thu Apr 02 17:55:29 EDT 2009 | smt_guy
Is there any effect when using Water Soluble Flux as they tend to be thicker and darker after reflow. How does AOI machines react to this? regards,
Electronics Forum | Tue Sep 22 14:18:27 EDT 2009 | davef
They could be correct about the silver if it weren't such a small portion of the connection. Study "electrochemical series of metals" to understand how metals react with each other.
Electronics Forum | Sat Oct 17 18:20:53 EDT 2009 | fulldrawmike
if your pneumatic cylinders are sluggish, try putting a few drops of 10wt air line oil in one and see how it reacts. The seals get dry and just can't move or at least that is what I have seen on equipment that does not use air line oilers.
Electronics Forum | Wed Dec 23 12:46:51 EST 2009 | stepheniii
Can you etch where you want to solder to? But you would need harsh chemicals to do that. The whole point of chrome is to not chemically react.
Electronics Forum | Fri Jun 15 11:22:14 EDT 2012 | hegemon
Good info above from davef Solder pot contamination seems likely, are you using any dross reducers or additives that might be reacting with this particluar batch of PWBs? 'hege
Electronics Forum | Tue Jun 18 11:47:02 EDT 2013 | dontfeedphils
Seems a little overboard. Maybe open up the machine and blow it out from time to time. In my experience, management likes to over-react to issues that would be considered anomalies and then try to lump them into PM issues.
Electronics Forum | Sat Sep 12 09:49:38 EDT 2015 | davef
If the boards were still "wet" after DI wash, your [I assume] low res flux could be reacting with the moisture on the board and causing the white spots. The preheater in the wave could have more dryification than the preheater on the selective solde
Electronics Forum | Thu Apr 18 23:56:27 EDT 2002 | Abelardo Rodriguez
I'm trying to get a better understanding of the cooking process of pcb's. The use of nitrogen in reflow and wave ovens. Seems to have a wide margin of acceptance as a standard gas to prevent oxidation of metals in the board. Has any one heard or us
Electronics Forum | Sat Jul 20 09:02:04 EDT 2002 | davef
Probably 2) what is this white residue material (chemically )? => Natural or synthetic rosin 3) Can Saponifier wash, helps? If not what is the best solution to remedy this white residue. => Probably a saponifier will work. Some NC flux residues
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