Cannot remove usb/lan port from motherboard

Discussion in 'General Electronics Chat' started by petkk1982, Apr 26, 2016.

  1. petkk1982

    Thread Starter New Member

    Apr 26, 2016
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    Hello,
    I bought a Tenma 60w soldering station. I am trying to remove a usb/lan port from a hp desktop motherboard(m2n68-la) but the solder joints just will not melt. The temperature on the display of the station says 400 c but when i checked the temperature of the tip with a infrared thermometer it only reads 150 c. It is a brand new soldering station so i don't imagine there is a problem with the heating element. Any ideas??????
     
  2. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    969
    touch some new solder to the tip.. does it melt quickly.. If so its hot enough..
    Is the connector through hole or surface mount?
    Sometimes adding a bit of solder to the joints will allow you to remove it easier..
     
  3. tracecom

    AAC Fanatic!

    Apr 16, 2010
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    Be sure the tip is tightly attached to the iron.
     
  4. petkk1982

    Thread Starter New Member

    Apr 26, 2016
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    Hello Mcgyvr thank you for your reply,

    Yes it melts quickly when tinning the tip so then its not the station I take it. The connector is through hole and i have tried adding a bit of solder to the joints. Is the factory based solder different?
     
  5. petkk1982

    Thread Starter New Member

    Apr 26, 2016
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    Hello Tracecom,

    The tip is properly fitted nice and tight
     
  6. atferrari

    AAC Fanatic!

    Jan 6, 2004
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    In my experience, those boards require lot of heat. There are many ways for it to escape; ground planes et al.

    Are you trying to salvage the connector? If so, use a heating gun to bring the whole area to a higher temperature.

    If still in doubt about the station, try to desolder something from a very small PCB.
     
  7. petkk1982

    Thread Starter New Member

    Apr 26, 2016
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    oK
     
  8. BR-549

    Well-Known Member

    Sep 22, 2013
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    Solder wick.
     
  9. MrSoftware

    Member

    Oct 29, 2013
    498
    122
    If there's a lot of copper in the board then it might be sucking the heat away faster than your iron is putting it in. This has happened to me when I worked on things with thick copper layers. This has helped me a TON. It has enough heat capacity to melt most joints quickly, and the solder just disappears when you pull the trigger. Fantastic for disassembling:

    http://www.amazon.com/Desoldering-S...1&redirect=true&ref_=oh_aui_search_detailpage
     
  10. petkk1982

    Thread Starter New Member

    Apr 26, 2016
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    Thank you i will have a look at that
     
  11. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    No its not.. Its probably lead free solder.. (SAC or K100 or similar).. In general they are all virtually identical but some difference that you don't need to worry about..

    The reason for adding some solder is to increase the heat transfer from tip to pin..
    When just a small portion of the tip is touching something the amount of contact surface area is quite low.. Adding solder at that point will effectively bridge between the pin and solder iron tip thus allowing more contact surface area between the 2..
    This will allow heat to transfer quicker from tip to pin..

    Of course as stated you could have large copper pours sucking the heat away,etc.. But I suspect its simply low surface contact/low heat transfer and old/oxidized solder,etc..

    Be very careful though.. Apply too much heat for too long and you will heat up the adhesive in the board and the pad/trace will lift right up off the substrate thus destroying the through hole plating as well as the board itself/ripping off the pad,etc..

    If I just had a soldering iron this is exactly how I would do it..
    #1-Go around and add fresh solder to each pin making sure its fully wetted..
    #2-Use a solder wick to pull out as much as possible.. (if it doesn't take it all out then add more solder .. yes more.. to that pin and try again)
    #3-Clean the holes using the same process after complete removal of the connector

    How I would do it with the tools I have..
    #1-Fire up the solder pot
    #2-Place the whole connector/pins into the molten solder and gently lift up removing the whole thing in one shot without damage.

    Well actually I would have just bought a new computer :D
     
  12. petkk1982

    Thread Starter New Member

    Apr 26, 2016
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    LOL... Great advice thank you
     
  13. Roderick Young

    Member

    Feb 22, 2015
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    If I had to preserve both board and connector, I would use solder wick, and additional liquid flux to clean each hole individually. It's a lot of work, but can be done if you keep at it. Let the iron get super hot, then work quickly on one hole. Then let the iron reheat.

    If I was replacing a connector, I would destroy the connector first. Cut it off with a diamond wheel and dremel tool, then remove each pin individually.

    If I was salvaging the connector only and didn't care about the board, I would clamp the board upright, grip the connector with pliers, and quickly heat the other side with a propane torch. This is how I salvaged components years ago when I was starting out.
     
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