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Discuss Not soldering in the Fittings & Pipes area at

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  1. Paul Cockhill

    Paul Cockhill Member


    Cannot understand why the solder is going into balls and dropping off the pipe. Must be making basic errors but cannot understand what. As the soldering yesterday was fine.

    Any ideas

  2. Rickster123

    Rickster123 Guest

    Pipes cleaned with wire wool? Properly fluxed up? Water in the pipework?
  3. Riley

    Riley Plumber GSR Top Contributor!!

    I'd say most likely water in pipe
  4. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    I would say pipe not clean as it's melting and dripping of and not sucking into joint
  5. jtsplumbing

    jtsplumbing Plumber GSR

    What sort of pipe are you trying to solder ??
  6. Stigster

    Stigster Plumber

    Overheating can cause this. As other's have said water in the pipe can also cause the opposite issue of not reaching soldering temperature and the solder will bead or run off.
  7. JCplumb

    JCplumb Plumber

    Had a spell of this happening when my flame was too hot, took a while to find the sweet spot with my new torch. The fittings were blacking up before reaching solder temperature.
  8. Howsie

    Howsie Plumber

    Pipe not cleaned or fluxed properly. Overheating burns all the flux off.
  9. Paul Cockhill

    Paul Cockhill Member

    copper pipe
  10. Paul Cockhill

    Paul Cockhill Member

    no water in the pipe
  11. Paul Cockhill

    Paul Cockhill Member

    Thanks everyone for your replies. It is copper pipe and it was cleaned and no water in the pipe, so i guess I have not fluxed enough
  12. scott_d

    scott_d Plumber GSR

    any pics?
  13. Howsie

    Howsie Plumber

    What gas are you using? What size pipe?
  14. Best

    Best Trusted Plumber Top Contributor!!

    Try not to heat the joint too much and keep adding flux on the end of the solder wire.
    When the solder wire just begins to start melting, (touching copper, but not under the flame), you are normally only 2 or 3 seconds from the correct temperature for soldering.
    If the clean pipe and fitting inside and outside hasn't been "tinned" (coated in solder) then it will not solder properly when the flame tarnishes it. That is why you need to keep the surfaces fluxed. Note that capillary action also works well with flux, so don't be afraid to add flux as you solder.
    • Like Like x 1
    Last edited: Jul 25, 2016
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