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water soluble flux recommendation?

Royboy Member Posts: 223
while flushing a new system today (with water & quasi-TSP) I thought about the idea of switching over to water soluble flux in order to presumably be able to better/more-easily clean out soldering residues.

I tried it a while back and didn't like my experience. my recollection is that the water-soluble flux I tried had a strong odor during sweating that I didn't want to have to work with day in and day out. so the mostly full container of it went in the trash and I went back to my tub of Nokorode regular.

anybody happy with a particular, hopefully not-too-stinky, brand of water soluble flux?


  • SpeyFitter
    SpeyFitter Member Posts: 422
    Aqua Pro 2000 by Whitlam

    The best water soluble flux I have found is by Whitlam called "Aqua Pro 2000."

    It is the flux that I've found that resembles anywhere near the performance of the acid based fluxes. I would say it is about 90%-95% in performance compared to the acid based fluxes. By that what I mean is I measure the performance of a flux by how it resists oxidation, and this is related to the room for error in how it can tolerate being overheated for those times when you may be in a tight spot and need to overheat one section of the joint to hopefully rely on capillary action to pull the solder in, as an example. This stuff is white and goopy and stays on the pipe nicely. It also doesn't stink and doesn't seem to sting as much as others if you get it in a cut or something like that.

    Now the Oatey water based - don't even get me started. Burns very easily, stinks to high heaven, and after you wipe it off, it makes the fitting look like chit!

    Just a note - I solder with a bucket of water near by. I then wring out a wet rag and wipe the joint after the solder has cooled slightly, and then I hit it with a dry rag after that. Makes the joints look really good.

    There is a chemical some guys use to flux freshly soldered systems is called "Fernox." Apparently it works wonders from what I have heard.
    Class 'A' Gas Fitter - Certified Hydronic Systems Designer - Journeyman Plumber
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
    Stick with the NoKorode...

    Water soluble flux has an extremely low frying point, and once fried, your joint is toast and will most probably leak. Such is the nature of the beast.

    Using NoKorode, when properly done, won't really place that much flux into the system. The key is proper application, and believe it or not, it is so thin, that you have to hold a fluxed pipe against an unfluxed pipe to see the difference.

    I developed a set of sponges, cut by extremely sharp copper tubing, that I brushed with flux, then use for fluxing the inside of the fittings. Thin thin thin.... The old adage of "If a little flux does a little good, then a LOT of flux must do a LOT of good" couldn't be further from the truth. The flux STAYS inside the pipe and causes corrosion, typically mistaken for hydraulic erosion corrosion, but not the same.

    I also developed another one, shaped like a crescent moon for fluxing the pipe. It sets in a crescent shaped piece of 2 X 4 with a 2 X 4 base to keep it upright. I brush the flux onto the sponge about every ten pipe applications. Then I roll the tubing end on the sponge and it applies a real thin coating of flux to the pipe.

    The amount of flux applied, as previously stated, is SO thin, you have to keep an eye on your work, because you can't see the flux with a naked eye, and that's a good thing.

    As you heat the joint, you will see it go through some phase changes. Follow the CDA recommendations of heating the pipe where the face of the fitting meet, then move your flame to the bottom of the solder cup, and KEEP IT MOVING.

    NEVER hold the flame in one spot for more than 1 second. One thousand one...

    When you see the flux go dry, it is time to back off the flame and move the solder into the joint. The worst thing you can do with any flux, is over heat the joint and oxidize the flux. Once oxidized, you are screwed. Ain't no amount of doctoring and re fluxing that is going to pull your bacon out of the fire. Start from scratch.

    This is based on MY 35 years worth of soldering, which I have modified over the years. I realize that a LOT of people have been soldering "their way" for a LONG time, but my method is tried and proven. Your milage may vary :-)


    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • MIke_Jonas
    MIke_Jonas Member Posts: 209
    You could always use ProPress

    Insert green, toothy-faced emoticon indicating humor/sarcasm here
  • TonyS
    TonyS Member Posts: 849
    Like Mark, I have been using

    No corrode for 30 years but have recently switched to No corrode water soluble. I have been very satisfied. It does turn the copper green fast if left on over night but the joints run well and I love how it washes off my hands and pipe.
  • Royboy
    Royboy Member Posts: 223
    thanks guys

    thinking I'll check out your sponge technique, Mark. sounds like an upgrade to the old flux brush, which sometimes results in more flux than needed.

    and maybe check out some NoKorode water soluble, when I next cross paths with it
  • Royboy
    Royboy Member Posts: 223

    is that emoticon green from seeping glycol?

    still soldering here ...
  • MIke_Jonas
    MIke_Jonas Member Posts: 209
    Can I call you Roy?

    Great minds think alike!!

    I thought that exact same glycol thing right as I was hitting the submit button.

    I thought..what are the chances he'll bring up green=glycol??? Nahhhh.

    You made me laugh out loud! (no glycol yet, but lots' o' Propress!)
  • bill_105
    bill_105 Member Posts: 429

    So I read this boring thread abot flux. And what comes to mind is this movie. We just saw it again last month. The first time was back in 1990.

    Four guys from Poland go to England and remodel an apartment (flat). Everything goes wrong. It's Moonlighting. Not that stupid tv thing with Willis And Sheperd

    One of the things is all the solder joints leaked. Good movie, Netflix has it.

     Then it hit me. (sorry an inside thing) My English teacher from high school told me about the movie. After high school we were way, way close starting in Berkeley. I swear I'm not making this up. None other than FRP.  And it wasn't M.R.   Still poking around though. Best of luck.
  • SpeyFitter
    SpeyFitter Member Posts: 422
    How much heat are you guys putting on your joints?

    I have had very few problems (tight spots/big pipe) putting too much heat and "frying joints" with water soluble whitlam Aqua Pro 2000. How much heat are you putting on your joints?  I've done entire restaurants in all copper and very, very few leaks.
    Class 'A' Gas Fitter - Certified Hydronic Systems Designer - Journeyman Plumber
This discussion has been closed.