[Need Help]Soldering problem

Discussion in 'The Projects Forum' started by newaisa, Jan 13, 2012.

  1. newaisa

    Thread Starter New Member

    Dec 6, 2011
    12
    0
    Hi guys,

    I am very new to soldering. I bought a prototype board trying to solder some very basic components into it. I found that the melted tin kept "sticking" to my solder gun instead of the board itself. I have watched several youtube video on how to solder. I followed what they did, but the tin will just "stick" to the gun all the time. What am I doing wrong here?

    Second problem is that, I couldn't rub off the remaining tin on the gun. I saw people took them off by just gently touching a soaked sponge.

    I tried reading some soldering guide but still couldn't pull it off. My solder just doesn't meet the "standard". The tin I applied is "floating" and not sitting on the board.

    I hope someone experienced can give me some guide.
     
  2. Skeebopstop

    Active Member

    Jan 9, 2009
    358
    3
    The trick to your problem is where to heat first. You have to apply some amount, albeit not too much so as to damage the component heating itself up through your pad contact, of heat to the pad first. You can generally also achieve marginal performance heating the pin first but more likely to damage the component.

    Basically, anywhere you 'heat' first will 'suck' the solder towards it. In this case your solder keeps getting sucked by the only 'hot surface' which is your soldering iron. Believe it or not the copper pads on the circuit board conduct heat better than your soldering iron (mind you they also cool quicker), so the solder should have a tendancy to prefer the pads. Generally speaking, using either 'solder flux' or solder which has a 'flux' core makes it basically impossible to miss, so I recommend you have a go with some flux before you master the mind of the solder. It takes some time and practice but eventually you'll be able to wield it to make jumper wires (to restricted lengths) and other such necessities to save the time of having to put down a precision wire to make certain connections.

    ANyways, soldering is great fun once you get the hang of it.
     
    newaisa likes this.
  3. newaisa

    Thread Starter New Member

    Dec 6, 2011
    12
    0
    thanks Skeebopstop, I was wondering does the board material matters? This is simply a matrix board I bought, and the datasheet says that board material is SRBP.

    I will try to heat the board first instead then, hopefully it didn't get damaged.

    And also, I am thinking of a cheap way to get an exhaust. The smoke of solder irritates me:(
     
  4. DickCappels

    Moderator

    Aug 21, 2008
    2,651
    632
    As a precaution, I would like to write some statements, just in to prevent a misunderstanding:

    Electrical soldering is best done with an alloy that is intended for use as an electrical solder -plain tin is not commonly used.

    Electrical soldering is to join to metal conductors together using solder. (You cannot solder to a fiberglass or phenolic circuit board if it does not have copper traces on it).

    Some metals are can not be readily soldered, Aluminum comes to mind, as it quickly forms an oxide film very quickly. Iron, (for reasons I cannot explain) will not "stick" to solder.

    The conductors to be soldered should be bright and clean, and free of oxide or other surface films.

    Solder flux is very important in obtaining a good solder joint. Often, "flux core" solder is used.

    Some solder should stick to your soldering iron. This is good as it helps reduce oxidation of the tip.
     
  5. bwack

    Active Member

    Nov 15, 2011
    107
    10
    If its one of those brown prototype boards, or veroboards, rub the copper with fine sandpaper to remove oxidation, then try soldering again.
    when sandpaper is used, oxidation will happen even quicker, so if you have flux or liquid tin laying around, apply it to the copper as quick as possible to protect it.
     
  6. DerStrom8

    Well-Known Member

    Feb 20, 2011
    2,428
    1,328
    What kind of solder gun do you have?

    On a regular soldering iron, the key to keeping the tip from burning up and keep the solder from "balling up" is to tin it while it's heating up. This should create a nice, smooth covering to the iron made of solder, and it allows better heat transfer.
    It is also important to know that in most cases, the solder should not ever touch the iron's tip. You may have to tap it quickly to get it to start to flow, but the solder should really only need to be touched to the component lead itself.

    Usually if the solder is balling up on the soldering iron's tip, it means it is too hot. A 15 watt iron is good for soldering average-sized components. Anything higher is unnecessary, and sometimes can even destroy your components.

    So, in summary:

    1: Make sure your iron is <20 watts (depending on the size of your components
    2: Tin the soldering iron while it's heating up
    3: Do not touch the solder to the iron

    I hope this helps.
    Regards,
    Der Strom
     
  7. Adjuster

    Well-Known Member

    Dec 26, 2010
    2,147
    300
    There is a type of soldering iron that really does look a bit like a gun. Typically, it has about a 100W rating. It looks something like this: http://www.elexp.com/sdr_d650.htm

    These are best used for heavier jobs only. They are not really suitable for light board work as they can produce far too much heat.

    A much smaller iron is better for most electronic jobs: a basic hobbyist iron of about 20W or less* would be OK. The ideal might be a temperature-controlled model of somewhat bigger wattage. These are expensive though, and maybe not a wise thing to buy if you are just beginning and uncertain how committed you are to the hobby.

    *But I'm not keen on using too small an iron either: paradoxically they can overheat things too, because the solder may take so long to melt that the heat will spread much too far.
     
Loading...