Electronics Forum | Fri Apr 09 09:08:40 EDT 2010 | cast2010
Hello, I produce two types of board. - 100% Thru Hole - 50% thru hole and 50% SMT For the second, I have a bad wetting after the reflow on the top. The pcb board have Au-Ni pad. I use a water soluble paste. I clean the board with a solution with
Electronics Forum | Fri Apr 09 20:47:36 EDT 2010 | 89jeong
I think the oxidation on the pad happens easily but do not on Au plated pad.The reason may be caused by improper cleaning or Au plating thickness in plating process. But,before suspecting the pcb board, you need to check your process or used material
Electronics Forum | Fri Apr 09 15:00:04 EDT 2010 | davef
So for your SMT1/SMT2/PTH boards, you have poor solderability during SMT2. [Even if you have no SMT2 and only ST1/PTH, our answer is the same.] We assume this occurs on one board part number only. We guess that your bare boards have insufficient gol
Electronics Forum | Fri Apr 29 04:36:49 EDT 2011 | city4497s
Hi Anyone encounter this type of reflow issue before?
Electronics Forum | Fri Apr 29 08:28:17 EDT 2011 | markhoch
Is it possibly being caused by surface contaminants on your PCB? Or possibly flux residue? Is this a one time occurance, or are you seeing it regularly? Is it happening in other areas on your PCB or in just this location? Can you please provide more
Electronics Forum | Thu May 05 01:21:42 EDT 2011 | city4497s
Hi Davef The problem shows up on * random location including component pads * all PCB and different PCB supplier * different solder paste lot * both printing and dispensing process * all production shift * we have only 1 production line It black,
Electronics Forum | Tue May 03 20:01:24 EDT 2011 | city4497s
It a recent occurance and it happen randomly on other area. I'm using senju M705-GRN360-KV and Indium SMQ 90 Leadfree solder paste, we have been using both paste for 4~5 years. We have asked the oven supplier to perform maintenance and inspection, pr
Electronics Forum | Thu May 05 08:14:45 EDT 2011 | kahrpr
Where black pad exists, it is not a common problem. When I read it is totally random I doubt that. You have defiantly something going on that is unique with the process. It is either your board manufacturer or your solder paste or your profile. It c
Electronics Forum | Tue May 03 21:14:19 EDT 2011 | davef
Can we talk some to better understand the scope and breadth of the problem? * From your picture, it looks as if the problem shows-up on some pads, but not others. Is this accurate? * Is this lot related? * Is this related to a few items from a lot? *
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