Some flux questions

Discussion in 'Plumbing Forum, Professional & DIY Advice, Tips & ' started by jagermeister, Feb 27, 2014.

  1. jagermeister

    jagermeister New Member

    Messages:
    2
    Location:
    Colorado
    My first question is does flux go bad? I bought some flux about 8 years ago to do a repair job and was about to use it again. It doesn't look separated or anything. Just curious if the chemical composition degrades over time.

    Also, in doing some recent research, I've found that 'water soluble' flux is required for all potable water systems. Can anyone tell me if the flux I have is water soluble? It doesn't say as such on the container so I'm guessing it probably isn't.

    Rectorseal C-flux, Product Code 74026, Lead Free, Acid Free

    It was a plumber working at a big box retailer that initially sold me the flux for my repair project and, as it was lead free, I had assumed it was the correct stuff to use. If not water soluble, can someone recommend a good water soluble flux to use?

    Thanks for any help.
  2. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,251
    Location:
    Cave Creek, Arizona
    quote; recommend a good water soluble flux to use?

    In my opinion, using the words GOOD and WATER SOLUBLE in the same sentence is an oxymoron. There are "good" fluxes and there a "water soluble" ones. The water soluble fluxes are somewhat difficult to work with because they "burn" very easily and then the joint has to be taken apart and redone.
  3. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,804
    Location:
    New England
    For someone that doesn't solder pipe very often, the 'newer' water soluble fluxes ARE a pain. Your technique must be much better than with the older ones. I think those in a 'tinning' version (they have powdered solder in them) are a little more forgiving.
  4. DaveHo

    DaveHo New Member

    Messages:
    53
    Location:
    SE PA
    I'm with hj on this one. As a fairly experienced DIY'er, I've tried the water soluble fluxes & don't like them. Oatey #95 is all I use. Never had a bad joint with it.
  5. DoofusOfTheDay

    DoofusOfTheDay New Member

    Messages:
    34
    Location:
    Atlanta GA metro area
    What's wrong with the water soluble? Or what's better about the #95. I've used the water soluble and it works fine. What does the #95 offer that makes life easier?
  6. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,804
    Location:
    New England
  7. DoofusOfTheDay

    DoofusOfTheDay New Member

    Messages:
    34
    Location:
    Atlanta GA metro area
    Ah okay, well I'm no plumber but guess I have a feel for when it's hot enough, the copper starts turning color, etc.
  8. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,804
    Location:
    New England
    The other thing the tinning flux does is there's enough solder in it to coat the copper, minimizing the chance of it burning if the flux is all burned out...it is easier to use. Do you need it, certainly not, but for someone that does it rarely, it makes things easier.
  9. bluebinky

    bluebinky Member

    Messages:
    382
    Location:
    Santa Clara, CA
    I used water soluble flux on my last big project. It took a while to get used to lead-free solder and the flux -- a lot less forgiving than the old stuff. After a couple of practice joints, everything was fine. However about a year later when I tried to use it, the flux was bad. Don't remember that happening before...
  10. DoofusOfTheDay

    DoofusOfTheDay New Member

    Messages:
    34
    Location:
    Atlanta GA metro area
    Well shoot, I was I knew about the #95 all this time. I just grabbed the water soluble as it was there and available years ago when I first had the oppty to sweat pipes. Why does the water soluble exist if it is problematic or when is it supposed to be used?
  11. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,251
    Location:
    Cave Creek, Arizona
    quote; guess I have a feel for when it's hot enough, the copper starts turning color, etc.

    When you reach that stage, you have overheated the joint and your water soluble flus is burnt. It exists because bureaucrats, who know nothing about most things, thought it was a good idea to mandate it.
  12. DonL

    DonL Jack of all trades

    Messages:
    3,812
    Location:
    Houston, TX
    Flux does have a expiration date.

    hj hit the nail on the head.

    Anything that is "New and improved" to make your health better is a red flag.

    Water base flux will vaporize at a lower temperature.


    Put the lid on your flux and in the beer cooler for best results in storage.
  13. Terry

    Terry Administrator Staff Member

    Messages:
    14,763
    Location:
    Bothell, Washington
    I use water based flux, but then I've been soldering for years, so it works for me.
    I haven't used acid flux in decades.

    [​IMG]
  14. DonL

    DonL Jack of all trades

    Messages:
    3,812
    Location:
    Houston, TX

    It does work, and you have to use it being in the business.

    A homeowner can use Vaseline if they like, but code may not allow it.


    In that case KY works fair and is safe.
  15. Terry

    Terry Administrator Staff Member

    Messages:
    14,763
    Location:
    Bothell, Washington
    I have never tried that. How does that work? And what is the working ingrediant?
    I don't think they sell that where I buy my supplies.
  16. DoofusOfTheDay

    DoofusOfTheDay New Member

    Messages:
    34
    Location:
    Atlanta GA metro area
    Hmm, seems to work okay for me. Haven't had an issue. So was water soluble flux made because the guvment thought it would be less toxic or something? I seriously don't know why there is water soluble if #95 is so much better and easier.
  17. Terry

    Terry Administrator Staff Member

    Messages:
    14,763
    Location:
    Bothell, Washington
    Acid flux was eating away the copper in the joint.

    http://www.copper.org/about/pressreleases/1997/IndustryUpdate.html

  18. DonL

    DonL Jack of all trades

    Messages:
    3,812
    Location:
    Houston, TX

    Not really sure but the inert ingredient is water. Just add pipe.

    I have made many joints using no flux at all.

    Good Prep Cleaning and keeping the torch out of the area where you add solder works. Let a good solder do the work.

    I have seen acid core solder and flux eat on copper, The flux needs to be cleaned off.

    Your kit was missing Safety glasses, They are a must in my book.


    I am no pro, as you know.
    Last edited: Mar 2, 2014
  19. BobL43

    BobL43 DIY Senior Member

    Messages:
    1,786
    Location:
    Long Island, NY
    if you use KY and get the job inspected Don, you're screwed. Be careful. It's only allowed in Louisville and Lexington Kentucky.:p
  20. BobL43

    BobL43 DIY Senior Member

    Messages:
    1,786
    Location:
    Long Island, NY
    Don, are you using 6/40 rosin flux electronics solder? Lol.
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