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    Desoldering help

    Hi. I'm new to soldering. I'm trying to remove a part from a board, so I can replace it with a new one, but I am having trouble trying to remove the old one. I have tried using flux with a de soldering braid, but it doesn't seem to want to remove all of it.

    Any suggestions?


    #2
    Re: Desoldering help

    I added a link for a picture, but I’m on mobile, so I hope it works.

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      #3
      Re: Desoldering help

      IHMO, removing solder to remove a part can be the wrong strategy. You want to flood the part with solder so that your iron makes excellent contact with the puddle and the puddle transmits the heat into the board. I'll desolder joints to remove parts, but it's pretty easy with a heated desolder gun or even a desolder plunger pump. If I didn't have either, I'd use some PB solder to bring the melt point down a bit, keep it molten while I back the part out. Then I'd clean the solder out afterwards. Or sometimes, on a particularly stubborn board, I might keep the puddle melted and insert the new part through it. Kind of a pain, but sometimes you have to do what you have to do.

      Of course, I'm assuming a two pin through hole device. I can't see any pics, so can't really give tailored advice.

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        #4
        Re: Desoldering help

        Picture

        I added a link to the picture on imgur.

        I was going to try that, but like I said, I’m new to soldering. I have a great soldering gun, and all the other stuff that is needed. From the picture, it looks like I’m getting to the bare bones, but I just can’t get that last little bit.

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          #5
          Re: Desoldering help

          that would remove easier with hot air . or maybe chipquik

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            #6
            Re: Desoldering help

            I'd use hot air to remove connectors, then braid to clean up the left over solder.

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              #7
              Re: Desoldering help

              Ok, how would I do that? I have a hot air gun. Would I just put flux on the contact points, and heat it up?

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                #8
                Re: Desoldering help

                Depending on the connector I add leaded solder or low melt solder using an iron. Then I use hot air to remove the connector. I don't use flux when removing stuff.

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                  #9
                  Re: Desoldering help

                  Ok, thanks for the ideas. I’ll give it a try tomorrow and see how I make out. The stuff on the top has come off, but not the bottom stuff.

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                    #10
                    Re: Desoldering help

                    Or if you have a soldering tweezers would also work but you would have to add some more solder to the mounting tabs and pins

                    Or remove the solder from the pins and add more solder to the tabs and remove the part when the solder has melted and is flowing

                    Which ever method you decide to do you will have to use more heat maybe as high as 800*F make sure your tweezers are up to temperature before you start

                    If you use a temperature controlled hot air gun turn up the heat and turn down the air flow but do not turn the air flow to low and do it from the back of the part too the edges of the board and keep moving around the part until it comes loose from the board
                    Last edited by sam_sam_sam; 10-04-2021, 06:16 PM.
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