Seeking solder no-clean flux recommendation

Discussion in 'General Electronics Chat' started by Involute, Dec 26, 2016.

  1. Involute

    Thread Starter AAC Fanatic!

    Mar 23, 2008
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    My standard soldering "recipe" is Kester 245 flux cored solder with Kester 951 liquid flux. Most of my work is SMD by hand (little through-hole, no reflow). My goal is as pristine a PCB as possible after soldering, with as little post-processing as possible. Nevertheless, while Kester describes the results of 245 as "visually acceptable," there's still plenty of residue (either from the 245 or 951), most of which comes off with some mild isopropyl scrubbing with an anti-static brush. Unless I put in a lot of effort, there's still residue visible. Just wondering if someone here has a better recipe/process. Thanks.
     
    Last edited: Dec 26, 2016
  2. dl324

    AAC Fanatic!

    Mar 30, 2015
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    I do most of the cleaning with 90-99% IPA and a short bristle horse hair brush and finish with an aerosol flux remover.
     
  3. Involute

    Thread Starter AAC Fanatic!

    Mar 23, 2008
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    Such as?
     
  4. dl324

    AAC Fanatic!

    Mar 30, 2015
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    I use MG Chemicals Flux Remover For PC Boards.
     
  5. Dr.killjoy

    Senior Member

    Apr 28, 2013
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    There is no really bad company to use for Flux remover ..
    +1 @dl324
    90-99% IPA same for me
    I buy big bottles at Walmart for cheap..
     
  6. Kermit2

    AAC Fanatic!

    Feb 5, 2010
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    The residue is dissolved flux deposited when the solvent evaporates. The alcohol dries to fast to get it all off.

    To get the pristine condition you prize will require a running liquid bath of pure solvent and a work station akin to a "parts washer" like those found in an auto mechanic's workshop.

    Also, some flux formulas are made water soluble, so a 90% or purer alcohol will be less effective than a 50 to 70% mix.
     
  7. RichardO

    Late Member

    May 4, 2013
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    I have a glass, cake baking pan that I put about 3/8" to 1/2" deep with alcohol. Soaking a PCB in that for a few minutes followed by a slight scrub with a flux brush is usually enough to do the job. When I am done, I put the used liquid into a bottle labeled "used" for using again later.

    Good hint on the water in lower percent alcohol being better for water soluble fluxes.
     
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