Soldering help needed, solder not working as expected.

Discussion in 'General Electronics Chat' started by calibre, Nov 9, 2015.

  1. calibre

    Thread Starter New Member

    Nov 9, 2015
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    Hi guys,

    I'm really frustrated as nothing seems to be working.

    I bought a soldering iron that came with some lead and tin solder wire and also bought some silver solder paste.

    I've been trying a to do a few things with this, but it's just not working.

    The first project is I'm trying to attack copper feet to a copper plate, however when I do this the solder melts and turns into little balls.

    The second project is that I'm trying to repair some electronic wire.

    I watched this youtube video, and it looked like it worked like magic.



    However I bought some flux, http://www.ebay.co.uk/itm/40g-tin-s...lectronics-SMD-plumbing-DIY-etc-/121026854235 that one, and it doesn't draw in the solder like a magnet, like in the youtube video.

    It still just turns into little balls and doesn't stick.

    I really want it so that I just touch it, and it absorbs into the flux that I've applied, like it does in the video.

    Any help on this will be appreciated on what I'm doing wrong and how to make it work, as I'm so stressed about this.

    Also I've sanded down my soldering iron tip with sand paper, to make it sharper, however I've read now doing this is bad. Have I destroyed my brand new soldering iron?
     
  2. dl324

    Distinguished Member

    Mar 30, 2015
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    Make sure the surfaces to be soldered are clean and hot enough to melt solder before applying any. Apply the solder to one of the parts to be soldered and let the solder flow into the joint.

    Don't sand or file your tip if it's plated.
     
  3. calibre

    Thread Starter New Member

    Nov 9, 2015
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    I'm pretty sure it's hot enough. As the solder is melting, but not sticking, and it just turns into little liquid balls.

    As for clean enough, I'm not sure how to do this. This is what the flux is for? Have I got the wrong flux?

    Why isn't it working the same as in the video I watched.
     
  4. gerty

    AAC Fanatic!

    Aug 30, 2007
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    Also, in the title line description for your flux it says plumbing...That would be acid core flux.... not what you need .. you need rosin flux, if that's what the container says you're ok. But like dl324 said, you must get the wire hot first...
     
  5. dl324

    Distinguished Member

    Mar 30, 2015
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    If you're applying solder to the iron, it will melt even if the things you're trying to solder aren't hot enough. The balling is an indication of the temperature being too low or the parts not being prepped properly.
    Flux will remove some oxidation, but it's best to use some abrasive to make the copper bright before soldering. Look for videos on how plumbers solder copper pipes and you'll see that they always sand before applying flux and soldering.
    The video looks like it's for soldering wires. You're soldering something that needs a lot more heat and your iron may be insufficient.
     
  6. calibre

    Thread Starter New Member

    Nov 9, 2015
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    Hi, I'm not too sure what flux I have, the ebay title said "40g tin soldering flux paste for electronics SMD plumbing DIY".

    Because it said electronics, I thought it's the correct one. The tin isn't in English. Only thing that is in English is, "Medium-Active flux that facilitates soldering of the following elements: Copper, silver-plated, zinc-coated and nickel-plated, used in places where rosin is not sufficent."
     
  7. calibre

    Thread Starter New Member

    Nov 9, 2015
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    I want to solder wires as one project and the second project is to solder copper feet on a copper plate.
     
  8. calibre

    Thread Starter New Member

    Nov 9, 2015
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    The soldering iron I bought is 40w, 220 - 240V Ac.
     
  9. shortbus

    AAC Fanatic!

    Sep 30, 2009
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    Your second project, I doubt if a small soldering iron will be enough. Copper conducts heat very well, so an iron made for electronics/wires is small compared to plumbing joints. Your copper plate and feet will probably take a propane torch to get enough heat.

    You always add the solder to the joint, not to the irons tip. The solder won't stick to the joint until the actual joint is hot enough.
     
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  10. calibre

    Thread Starter New Member

    Nov 9, 2015
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    Also, if I have got the wrong flux, does it have different properties to rosin flux?

    Will my solder be drawn in and absorbed into the wire like the video? Or would it be the same results as the wrong flux that I'm using.
     
  11. calibre

    Thread Starter New Member

    Nov 9, 2015
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    Hi, the second project is a bit complicated, it's basicly the same as this:-

    What I'm trying to do is half the size and one side must not be burnt.

    What I thought happens, is that I apply flux to the area I want the solder to be drawn into, and the solder flows into the spot where I've applied the flux to.
     
  12. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    Your tip is already destroyed as you sanded it thus removing the top layer and possibly iron layer..
    Its not a "knife" you don't need a sharp tip. Never do that.. get a new tip
    More than likely the tip is destroyed and you can't get good heat transfer from tip to whatever you are trying to solder..

    If you are getting solder balls forming on the material then
    #1-Your item is not hot enough
    #2-Your item is too dirty/oxidized
    and its probably both.. but more #1 than anything

    Most electronics solder already contains flux.. But it never hurts to apply more provided you are activating it properly.. Its corrosive and will cause problems if not activated or removed post soldering (assuming its not no-clean flux and was activated)
    Typical flux is activated by heat.. which evaporates out the solvents leaving it mostly inert (no-clean again).. It should not be sticky after soldering and virtually invisible..


    Copper feet/plate (have NO idea how big these are) may require considerable time and a very large iron to provide sufficient heat..
    A torch/flame may be better (like plumbing soldering)..
    If you attempted plumbing with a typical soldering iron you would be there for days..

    Copper is very conductive (thermally as well as electrically) so its rapidly absorbing and spreading the heat..
    I can take a regular soldering iron and stick it to a copper bar and watch the temp of the soldering iron drop to almost nothing as the soldering station does not have enough power to provide the needed heat and allow it to reheat fast enough.. The copper is literally sucking the heat out faster than the iron can provide the heat..


    When all is right the solder will flow like thick water.. If its not.. Its not hot enough..

    Note.. You could also just have a bad batch/old solder.. It happens..
    Typically this shows as "peaky" solder where it will stick to the iron and form peaks like cake icing..
     
  13. calibre

    Thread Starter New Member

    Nov 9, 2015
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