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Anyone have any idea how I could remove this component?

I've tried blowing hot air, used solder wick, tried to poke the holes with two soldering irons, cut the pins to near the PCB, but it won't budge.

It would be ideal if I had a rectangular piece of metal that could get up to around 380 degrees celsius and that I can just place on the pins all the while pulling to remove the component.

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    \$\begingroup\$ Solder wick is the wrong direction. If anything, you need more solder and heat. \$\endgroup\$
    – JRE
    Jun 18, 2019 at 17:13
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    \$\begingroup\$ Good idea to invest in a $100 hot air gun. It makes this kind of thing trivial. \$\endgroup\$
    – efox29
    Jun 18, 2019 at 17:21
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    \$\begingroup\$ That's a good idea. Components would be fried afterward with one of those, right? \$\endgroup\$
    – mikanim
    Jun 18, 2019 at 17:23
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    \$\begingroup\$ you can buy special "desoldering" solder that lowers the melting point of regular solder .... here is a usage video youtube.com/watch?v=ekndTIjEw9E \$\endgroup\$
    – jsotola
    Jun 18, 2019 at 17:50
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    \$\begingroup\$ Do you want to desolder this component because you want to replace it? Or, because you want salvage components (and you don't really care about the PCB)? \$\endgroup\$ Jun 19, 2019 at 1:32

9 Answers 9

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You need a lot more solder, so as to cover all the eight contacts and heat them to their melting point. Think "solder pool." Once you pull the component, then you can remove the solder pool using whatever means you have at hand.

As the comments attest, this will make the part very hot. Silicone gloves have come to the rescue when desoldering large parts, for me.

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    \$\begingroup\$ avoid using your bare hands because the heat will be on the metal can and it will burn - continue to make that mistake \$\endgroup\$
    – efox29
    Jun 18, 2019 at 17:20
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    \$\begingroup\$ This did the trick. Many thanks. I spent about 2 hours trying to get that thing off and the solder pool only took about 5 minutes (4 minutes due to a false start and just getting the solder prepared, and only a few seconds to pull the component off). \$\endgroup\$
    – mikanim
    Jun 18, 2019 at 18:17
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    \$\begingroup\$ If gloves are not to hand, then pliers (or tweezers, depending on the tweezers) work well for me almost every time. In fact, I've used pliers more than I have used gloves - its only a bit more awkward to position it, but its great in a pinch. \$\endgroup\$
    – QuickishFM
    Jun 19, 2019 at 12:12
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    \$\begingroup\$ @QuickishFM I see what you did there :-) \$\endgroup\$
    – bitsmack
    Jun 19, 2019 at 15:55
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With big through-hole parts, I attack one pin at a time with a solder sucker (or "solder pump"). I prefer this type

ss

because they're big and cheap! It can remove more solder per use than the smaller, more refined pumps.

  1. First, you heat up the pin and melt the solder around it. You want to keep adding heat until the entire volume of the PTH is molten. It can help to add solder to improve heat flow.

  2. Then, use the pump to remove the solder. Don't remove the iron from the pin until after you use the pump.

  3. If the PTH looks empty, move on to the next pin. If there is still solder left over, fill it up with new solder (and flux) and try again.

  4. There will always be just a little solder left over holding one edge of the pin to the inner edge of the PTH. Here's the trick: grab each pin with the tip of some needle-nosed pliers and wiggle it until it breaks free.

  5. Once all the pins are loose, pull out the chip.

  6. Touch each hole with a clean soldering iron to reflow the remaining solder. There should be so little solder left that this action effectively clears out the holes.

In this specific case, you may have a problem with Step 4 since you have clipped the pins. Perhaps there will still be enough to grab onto.

And, of course, this makes a mess of the device's pins, so it shouldn't be done if you want to re-use the part.

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  • \$\begingroup\$ I actually have this exact one and tried it before making this post. It helped but I was already in the negative since I used hot air beforehand. +1 nonetheless for the detailed explanation. The solder pool worked in the end. I recommend trying bitsmack's answer first since it could be fairly easy with the pump BUT it could also rip out the inner copper housing/pad if the component gets pulled out with too much force or is still quite hot from the soldering iron. \$\endgroup\$
    – mikanim
    Jun 18, 2019 at 18:30
  • \$\begingroup\$ I'm glad it worked out! @TomServo 's "solder pool" technique is a good idea :) \$\endgroup\$
    – bitsmack
    Jun 18, 2019 at 18:33
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    \$\begingroup\$ I have done exactly this many times. \$\endgroup\$ Jun 19, 2019 at 12:14
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Dremel off the body, and get the pins one at a time with an iron. Clean up with a solder sucker and braid.

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For something like that, conventional soldering tools are the wrong answer. Possibly, a very high powered hot air rework station would do it, and could be the right choice if you need to work around other components that shouldn't be dismounted, but unless you already have it or are seeking an excuse to buy one, it's probably not the solution.

For something large on a sparsely populated board what you probably want is a hardware store type heat gun.

If you don't particularly care about the board, the old school method was a propane torch; beware the board will probably catch fire, and you don't want to breathe that.

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    \$\begingroup\$ I am curious about the propane torch, I would say it destroys both the board and the component... What's the point then? \$\endgroup\$ Jun 19, 2019 at 17:45
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    \$\begingroup\$ @VladimirCravero no, not at all, used properly it's not really any more likely to destroy the component than any other heat source. The question is about a through-hole component, so of course you use the torch on the back side of the board. Of course it's for the case where you want to salvage the component, not the board. \$\endgroup\$ Jun 19, 2019 at 19:07
  • \$\begingroup\$ Thanks, understood. \$\endgroup\$ Jun 20, 2019 at 8:02
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It looks like you have a hot-air gun. This should make the process fairly painless. (Unless you touch something hot, of course!)

I would try to suspend the board to ensure the component isn't touching anything. Then heat up the pins on the back of the board with your hot air gun. When the solder melts, the component's weight should cause it to fall away from the board.

One pin looks like it's tied directly to the ground plane, and a few others might be tied to a copper fill on the component side of the board. These will require a lot of heat: the whole plane needs to get hot before the solder joints will melt.

If the solder melts but the chip doesn't fall off, I recommend poking the pins with a thin wooden dowel (or a toothpick). The wood might start to smolder, but I haven't had one catch fire yet :)

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You can also try Chip Quick, it's a low temperature solder. It stays hotter longer. I use it a lot specially when I want to save the component I'm removing. It costs a lot but it works really well.

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    \$\begingroup\$ It stays liquid longer. \$\endgroup\$
    – JRE
    Jun 19, 2019 at 13:12
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    \$\begingroup\$ @JRE bingo! It stays liquid longer because of some melting point lowering, but it also changes the alloy enough such that there is no longer a eutectic point, and it goes through a slurry stage where you can still move stuff around. 60/40 lead-tin, and whatever alloy-from-hell is used for Ag-Sn solder is eutectic -- going directly from solid to liquid and back again-- with no slurry. \$\endgroup\$ Jun 19, 2019 at 17:36
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I would just use a hot air solder machine. May not be the conventional way but you will find it 100x easier. Just make sure to keep the hot air moving so you don't leave a burn mark on the pcb. If you don't own a hot air solder machine I would recommend buying one since most components these days are smt based and then you would have the ability to fix both styles of components.

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  • \$\begingroup\$ Most SMT parts can be soldered and removed with nothing more than a plain old soldering iron. \$\endgroup\$
    – JRE
    Jun 19, 2019 at 14:36
  • \$\begingroup\$ @JRE No, that's not really true. No good way to get QFN's off without making a mess, and trying to put on replacements is a pain especially if the board design doesn't extend the pads. The amount of effort wasted and scrap produced trying to avoid such a simple inexpensive everyday tool is a bit ridiculous, something realized once you have one. With care you can sometimes even do things that "shouldn't work" like fix a badly mounted BGA by heating it up and lightly bumping it. That said, a basic one may not be enough for this part; it's the rare case where a heat gun might be better. \$\endgroup\$ Jun 19, 2019 at 19:24
  • \$\begingroup\$ I don't recommend using a hot air solder machine. I did use one before asking for help. It didn't work since the area of the air is smaller than the are of the pins. Also a lot of the air is wasted i.e. takes a long time to make everything hot enough. So long to where the copper housing begins to give way and then the PCB is ruined. Too much heat for too long risks pulling out the housing and other parts of metal on the PCB. \$\endgroup\$
    – mikanim
    Jun 19, 2019 at 19:29
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Here's an idea and one that works for electronic companies. I use my electric fan oven and put it on its lowest heat and bake the board so it reaches a good temperature, roughly between 80 and 120 degrees. Keep raising it until the board it too hot to touch. Get everything prepared, flux, braid, sucker, gloves and what ever else you use. If the oven is close to you, the better. Try and find a small gap under the component and run flux and begin desoldering. It may take a few goes and you may need to place it back in the oven as the board will cool down. But make sure when the pins have desoldered that they move in the holes and then do the top. It's all about keeping a constant heat. You'll find your own way and technique, but I find it so invaluable. I'm sorry I can't help you if your oven is too far away. This is an idea that seems to work and I hope it helps you and anybody else. Have fun......

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You need to use flux. It reduces the melting point of the solder. People who say "add solder" are merely getting their flux from the hollow wire core. Too much flux is hard to get hot as it boils. Too little doesn't last long.

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    \$\begingroup\$ Flux does not reduce melting point. It cleans oxides at the surface, improving wetting, and maybe heat transfer. \$\endgroup\$ Jun 19, 2019 at 12:57
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    \$\begingroup\$ Flux activates below the melting point of solder. \$\endgroup\$ Jun 19, 2019 at 12:59
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    \$\begingroup\$ Another victim of the "use more flux" school of thought - who doesn't even know what flux is for. \$\endgroup\$
    – JRE
    Jun 19, 2019 at 13:11
  • \$\begingroup\$ @ScottSeidman while I agree this isn't the right answer, to an extent flux actually does reduce the melting point back to what it is supposed to be, by getting rid of the much higher melting point dross. \$\endgroup\$ Jun 19, 2019 at 19:27
  • \$\begingroup\$ @ChrisStratton -- I don't believe the dross would raise the melting point of the solder, as it's not in alloy with it, but it could certainly impact how much heat you need to provide to raise the solder to melting point -- thermal conductivity and mass issues moreso than melting point. Not much of a practical difference from the point of view of the person holding the iron, I suppose. \$\endgroup\$ Jun 20, 2019 at 12:35

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