Homebrew PCBs

(4) Wipe board with acetone (plenty of acetone), let evaporate.

I'd like to point out that Acetone does leave a film.  You might try Methanol dried with air.  The method we used to use for manual large area glass cleaning  was Trichloroethelene (degreaser) + Acetone + Liquid Freon (effectively banned) and blow off with a filtered air gun. 

I doubt that changing the cleaning technique would help.  The film might actually be beneficial.  The film has a measurable resistance on glass when measured with an electrometer.  A few picoamps at 100 V.

          
              
    
  

  

  
 



      

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