Electronics Forum | Fri May 25 13:24:38 EDT 2007 | mfgengr
I had a similar problem a long time ago. I eventually traced the problem to undercured solder resist. The flux was reacting with what was left of the uncured resist, leaving a white residue. We could not even hand scrub this off. The solution was to
Electronics Forum | Thu May 24 23:07:55 EDT 2007 | colormaker
Our filter removes all contaminates authou it takes forever to evaporate 20 gallons it work quite well. I will check with local water supply for mineral analysis. Will a water softener remove the minerals that may be causing the problem ?
Electronics Forum | Fri May 25 13:32:26 EDT 2007 | colormaker
We have 4 diffrent boards that have the problem. The boards have two diffrent suppliers. I dont think this is the case. I more leaning toward not enough rinse cycles in the washer. Jerry
Electronics Forum | Wed Aug 27 09:31:25 EDT 2003 | caldon
BMAN.........Consider yourself shot down. unfortunatly (for you) Mike and Ken are right on the mark. The root of your problem is the current system you have for stencil wash...Explain what Maintenance headaches you have. Many moons ago I had a Smar
Electronics Forum | Thu May 24 14:44:42 EDT 2007 | colormaker
We use a washer soluable solder flux for our solder wave. We then wash the boards in a dishwasher. We have done it this way for years without problems. We just got a new dishwasher and now we get residue on the solder (white marks) Anyone know of wh
Electronics Forum | Fri Mar 19 14:31:43 EST 2004 | pdeuel
DI water de-ionized water is an easier way to ensure washing free of contaminates. De-ionized water has a characteristic resistance of 18 meg ohms per cm squared. Resistance monitors can be installed in cascading wash systems that would monitor conta
Electronics Forum | Thu May 24 22:46:10 EDT 2007 | colormaker
The waste water is filtered then sent to city sewer. When we first started we had inspections and then they said our volume was so low and did not require continued testing. We wash 20-40 boards a month. Small 3x4 inch boards. If we hand rinse the b
Electronics Forum | Tue May 29 15:10:30 EDT 2007 | realchunks
Hi Jerry, Sounds like the white stuff is flux. I doubt if 4 pcb mfgers could be undercuring all at once. Good point though. Since you changed washers and now have the problem - it's your new washer. Can you bring back the old one to make sure?
Electronics Forum | Wed Aug 27 00:45:35 EDT 2003 | kenBliss
Bman Each area and process has a unique machine for a reason. Professional engineers at the various OEM�s have thought these things through and there are specific reasons why you don't wash stencils in a board washer, bake pizzas in your reflow ove
Electronics Forum | Tue Feb 01 12:02:56 EST 2000 | Mike Konrad
Your question may be answered in two parts. First, if you are using a water soluble (OA) paste, then water is an excellent �solvent�. Water, in one way or another, is used to clean all fluxes and pastes from PCB�s. In some cases, a chemical is add
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