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The title kind of says it all. I've been buying these prototyping/breakout boards and they come with a bunch pin headers that I don't want to be there because I want to mount them in my own way. Every single time I try to de-solder these pin headers I end up screwing up the pads on one side or the other. This seems to render the boards useless.

I'm using flux -- lots of it. I'm using a solder-sucker first. Then I'm using braid. Finally, I use the iron to push them out from the backside.

It's not always, but I'd say 20% of the time a pad comes out with the pin header I'm trying to remove.

Is there some trick to this that I'm missing here?

EDIT to Add:

Second pin from the top is lifted from the PCB, Third pin from the top, the pad is just gone.

I tried SO hard on this one. 325C on the iron, hot air gun, rubber bands to pull the pins out, but second pin from the top is lifted from the PCB, third pin from the top, the pad is just gone. I still have lifted or missing pads! Low temp. Extreme patience. Tried the hot air gun. I still end up with these kinds of results. I expect these boards to be crap, but I usually expect stuff to be de-solder-able somehow!

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    \$\begingroup\$ Turn the board upside down and use hot air. Once the solder melts gravity will pull the header to the floor. \$\endgroup\$ Commented May 14 at 14:29
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    \$\begingroup\$ You might be either applying too much force too soon (before the solder melts completely) and thus pulling at the pad together with the pin, or you might be applying too much heat, destroying the glue holding the pad to the substrate. Any chance you could add a photo? \$\endgroup\$
    – TooTea
    Commented May 14 at 14:30
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    \$\begingroup\$ Any reason you can't just buy the breakout board with out the headers already installed? They're usually easier to find as bare PCBs. If not, you could try turning the temperature down on the iron. \$\endgroup\$
    – MOSFET
    Commented May 14 at 14:45
  • \$\begingroup\$ Getting it without the headers is 4x the price. I mean, sure, I can bite the bullet on the cost, but I'd still like to add this skill, whatever it is, to my repertoire. Using hot air was looking promising until I cooked an electrolytic capacitor. :( What kind of temp would you use for de-soldering? \$\endgroup\$
    – ipmcc
    Commented May 14 at 14:48
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    \$\begingroup\$ Tried at a much lower temp. Still lifted pads. Maybe the boards are just too crappy. \$\endgroup\$
    – ipmcc
    Commented May 14 at 15:15

4 Answers 4

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Remove the pins first, then remove the solder.

Heat and melt the solder on one pin. Pull the pin out. It may help to add solder to each pin before removing it. Once all the pins are out, go back and use the solder sucker to clear the holes.


It shouldn't take any extra flux to remove the pins. Flux is to clean the metal surfaces you are joining - it makes the solder flow onto the metal better and form a better connection with the solder.

Extra solder helps because you need the solder on the entire soldered surface of the pin to melt at the same time. If you remove the solder first, you end up with little spots stuck to the pin and the pad.

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    \$\begingroup\$ And if pins inexplicably won't pull out of the plastic, the plastic can be cut between the pins. \$\endgroup\$ Commented May 14 at 14:51
  • \$\begingroup\$ Yeah, I get what you're saying about the flux, I'm pretty much just flailing at this point. \$\endgroup\$
    – ipmcc
    Commented May 14 at 15:04
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    \$\begingroup\$ @ipmcc If the solder is non-leaded, contaminate the solder joint with leaded solder or bismuth solder to lower the melting point. \$\endgroup\$
    – qrk
    Commented May 14 at 16:34
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    \$\begingroup\$ I disagree that adding flux is not necessary. Flux adds surface tension and improves wetting of the tip, vastly improving the thermal transfer from the tip to the joint. Adding solder can help when there isn’t enough solder for good thermal contact or to dilute lead-free solder with leaded solder. Otherwise, adding solder is mostly a proxy for adding flux. \$\endgroup\$ Commented May 15 at 2:42
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    \$\begingroup\$ @Kubahasn'tforgottenMonica Adding solder is also a way to add thermal mass, making it easier to achieve that the solder stays liquid on all the pins in a header at the same time. Otherwise, unless the header has just a few pins, it's a bit of a struggle to heat up the last pins before the first ones cool down and solidify again (because when that happens, it's a sure way to ruin the pads when you pull at the header). Applying copious amounts of extra solder even to the point where you bridge everything with a lake of molten solder is an easy (albeit somewhat wasteful) way to avoid this. \$\endgroup\$
    – TooTea
    Commented May 15 at 11:52
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You don't need tons off flux. If you do it right, the pin header can be de-soldered pretty easily. You can try this method.

  1. Apply some flux on the pins
  2. Apply solder on a thick copper wire or a bundle of twisted fine copper wires (see the top image).
  3. Set the temperature of your soldering iron to 300°C - 360°C.
  4. Use chisel or bevel tip with some solder applied to its tip.
  5. Run the hot tip along the side of copper wire back and forth while giving it some pressure (see the bottom image)

enter image description here

Make sure the iron tip is sufficiently hot. Otherwise you will struggle.

One of the easiest ways to clean and remove solder from through-holes is to dip solder wick in the flux (or spread some generous amount of flux paste on the solder wick) before wicking. For this to work well, you have to bump up the temperature to ~350°C.

If the pins are quite tight in the holes, you might need to gently pull it with a pair of tweezers from the opposite side. Here is a video showing the technique.

Regarding the high temperature used in these desoldering techniques, many people, including myself in the past, have expressed concern. What you don’t want to do is repeatedly heat the same spot for an extended period. The reason this mistake is made is due to insufficient heat. That was probably what you have done and suffered from damaged pads and whatnot. However, if you approach the task with a very hot iron tip and complete it quickly, you won’t harm the pads or the IC. Heat takes time to propagate, and also the temperature drops somewhat when the tip transfers its energy to the cold body it touches. Try touching a solder wick with your fingers at one end and a 360°C hot iron tip at the other end that is, say, 5cm away. It takes a few seconds before you feel the unbearable heat. If you can complete the job within that short period, you won’t cause any damage. If you fail in your first attempt, remove the iron tip and allow the heat to dissipate before trying again.

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  • \$\begingroup\$ +1. I support using higher temperatures. The main cause for damage is spending too much time heating the joints. Solder wick actually cools the joint and the iron. I now use 400 C except for very low thermal mass . It allows very short time interval. The wire adds thermal mass to counter the cooling effect of the pins \$\endgroup\$
    – RussellH
    Commented yesterday
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I'd simply remove the plastic strip from the row of header pins and the mount the board in such a way that the pins project out horizontally. You may need a vise for this. Then ensure that there is sufficient solder on soldering iron to conduct heat on to the pin. Grap the exposed end of a pin with tweezers (or fine point pliers) then lay the soldering iron on the side of the header pin between the tweezers and the board. The heat from the iron should then conduct through the header pin to the solder joint melting it and allow you to pull the pin out. Stainless steel tweezers may work best to avoid sinking too much heat from the iron. Once the pin is removed, clean up the solder from the pad using your favourite method.

To ensure that the plated through hole of the pad is sufficiently free of solder to permit the insertion of new header pin I sometimes add more solder to the pad, heat it well, then blow through a small pipe (of similar dimensions to a ball point pen) to clear all the solder. Beware, however, of solder splatter on the other side of the board.

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    \$\begingroup\$ The blowing is a cheapo trick, but can be substituted with a solder sucker or solder braid. I would also suggest using leaded solder to lower the melting point, and maybe decreasing the temperature to 300 ˚C. \$\endgroup\$
    – Uncle Dino
    Commented May 15 at 11:37
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Go at the board with diagonal cutters or nippers, cut everything off, and then remove one pin at a time

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  • \$\begingroup\$ The plastic base can be pried off using a small flat blade. \$\endgroup\$
    – RussellH
    Commented yesterday

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