Some grades of organic coatings can only survive one IR reflow.
          This means that after the first heat excursion the
          protective coat is gone and copper oxidation begins.  You
          need to use a grade that is designed to handle multiple heat
          excursions.  The problem with your boards right now is that
          they are obviously now oxidized.  The post SMT clean
          operation and any baking you did will have contributed to
          this.  I'm not sure of any fluxes that could wet such an
          oxidized surface.  I don't know if you will be able to use
          these boards, without damaging your SMT.  Recoating the
          boards involves among other things a microetch to clean the
          oxidation off of the copper.  If possible you might try to
          remove the SMT from the boards, recoat, then do SMT, then
          immediately to your manual soldering.  Very risky though,
          multiple recoatings of OPCs can overetch your plated
          through holes or do some other bad stuff to the surface of
          the board.  Talk to your bare board house that provided the
          boards.  I hate to say it, you might be better off salvaging
          what SMT you can, get new boards (with either a better ODP,
          or HASL), and restuffing.

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     We are having trouble soldering organic protective coated bare copper 
     boards. The difficulty is occurring with manual iron soldering in the 
     post wave/wash shop.
     The boards soldered fine in SMT, and then they were washed. They then 
     sat several weeks awaiting finalization of engineering changes and 
     receipt of the EC parts. Now we are having extreme difficulty getting 
     the solder to wet to the copper in the postmount shop.
     Does anyone have suggestions to overcome this problem? Would it be 
     feasible to recoat the bare copper when it's determined the boards 
     cannot be completed immediately? Does anyone have a suggested time 
     limit in which to complete soldering after the wash? Does anyone know 
     of aggressive flux cored solder wire which can promote wetting and 
     still meet Bellcore specifications?
     Any advice would be appreciated.
     
     Allen Ahlert
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