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I'm a beginner in soldering. I was trying to change the LED of my mouse, and I successfully removed it, but now I can't put in a new LED because there's solder stuck in a very small hole. I only have desoldering pump, no wick. I have been trying to remove it but failed. It is frustrating.

Any tips?

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  • \$\begingroup\$ " I only have desoldering pump" As in one of the crappy hand tools, or as in a desoldering station with vacuum? Using the latter is the most appropriate and IMO easiest method. So if that's what you got then the question is why it is failing- maybe you aren't heating the plating sufficiently - what's the temperature setting? \$\endgroup\$
    – Lundin
    Commented Jun 14 at 8:40
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    \$\begingroup\$ How small is small? We use a 0.15 mm (6 thou) drill which we turn by hand. \$\endgroup\$
    – C. Dunn
    Commented Jun 14 at 14:44
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    \$\begingroup\$ Try with a round teeth stick. Melt the solder with the iron and then quickly put the stick in the hole before it solidifies. \$\endgroup\$
    – Gos
    Commented Jun 15 at 12:30
  • \$\begingroup\$ @Lundin You can get crappy ones, but there are also good hand tools. I use an Engineer brand SS-02 regularly at work and it's orders of magnitude better than any other hand pump I've ever used. Good suction, a replaceable few millimeters of silicone tubing on the tip to seal around the joint, convenient size for single-handed operation. (no affiliation, I just use it and like it, and I think other people would be helped by knowing there are better options than the cheap ones.) \$\endgroup\$
    – Hearth
    Commented Jun 15 at 13:22
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    \$\begingroup\$ Why don't you heat up the solder and push the new led in? \$\endgroup\$
    – Florian F
    Commented Jun 16 at 16:45

6 Answers 6

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Counter intuitively, add more solder and then suck the solder out. The extra solder allows more contact with the iron, and allows heat to get into the hole and melt the solder better.

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    \$\begingroup\$ It also provides fresh flux, which can help greatly. +1 \$\endgroup\$ Commented Jun 13 at 21:23
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    \$\begingroup\$ Yeah - even one of those spring-powered suckers should be able to do the job no problem. Just make sure you have the solder and surrounding area hot enough (adding additional solder/flux is what helps this happen), and make sure the sucker has as good a "seal" as you can manage, and make sure you don't have anything blocking the back side of the board like a piece of paper, and press the button. Leave the iron on it when you do this. Wick would work, as would a pneumatic desoldering iron (sucks with venturi effect). \$\endgroup\$
    – Steve
    Commented Jun 15 at 2:55
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    \$\begingroup\$ Having a decent "blob" (don't overdo it) helps you keep the soldering iron out of the way ... you just need to have the tip touching some of the solder, and it'll conduct the heat to the rest pretty easily. \$\endgroup\$
    – Steve
    Commented Jun 15 at 2:58
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I find the tap method works well:

Hold the board with one hand a few inches above your workbench. Use the iron in your other hand to melt the solder. Before it has a chance to re-solidify, quickly tap the board on your workbench. I can perfectly clear a hole in even very challenging boards this way. Works much better than a desoldering pump or even wick.

Applying a bit of fresh solder first can help.

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    \$\begingroup\$ A great approach that also work for clearing solder off something the could easily melt, such as solder tags on switches. Getting the solder hot enough that you have enough time to then use a hand held 'sucker' often means the switch body starts to melt. Give it a whack, all gone. \$\endgroup\$ Commented Jun 14 at 11:11
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    \$\begingroup\$ If you can't 'tap' it, you may be able to melt thensoldernwithnthebiron (maybe add a little more solder to give it some bulk), and then blow strongly into it at the instant you remove the soldering iron. \$\endgroup\$
    – jp314
    Commented Jun 15 at 10:53
  • \$\begingroup\$ @jp314 Blowing may not be enough but using canned air or a compressed air line does work. It is prudent to do this where the flying solder will not contaminate expensive test instruments or other circuitry like below table height. \$\endgroup\$
    – KalleMP
    Commented Jun 16 at 15:15
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Generally you can do without the solder pump, add more solder on the bottom so both pins are shorted and a blob is formed, melt with the iron and push the LED thru the melted solder, after that you just use the tip of the iron to remove the remaining solder, you gonna be left with a perfectly soldered LED.

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Certain metals, including steel, are quite resistant to solder. So one method is to find a pin, needle, paperclip or whatever is the right size for the hole. Then melt the solder and push the item through the hole.

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    \$\begingroup\$ zinc-plated paperclips take solder very easily. bamboo skewers work quite well for clearing holes. \$\endgroup\$ Commented Jun 14 at 4:39
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A nice solution not mentioned yet is to use desoldering needles. picture of a case containing a set of desoldering needles

These are stainless steel needles. Tin will not stick to them. You can heat the stuck tin, and then poke one of these needles through the hole to poke the tin out.

Another use case for desoldering needles is to remove through-hole components. You'd select a needle sized so it just fits over the component leg. Then when heating the tin you can slip the needle between the PCB and the component leg. When the tin cools and you remove the needle it will leave a ring-shaped hole in the tin around the component leg.

You can find these needles in various places online and they aren't expensive at all. They are somewhat disposable though, it's quite easy to break them while in use.

In my experience using desoldering needles is by far the easiest desoldering method available assuming you've got one in the right size.

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    \$\begingroup\$ Those are definitely useful for fiddling with a wire-end on occasion, but OTOH (a) are still too large for any but the largest PCB holes and (b) even without wetting do tend to conduct a lot of heat from the joint. That probably leaves a bamboo skewer or whatever ("matchwood" in fine mechanical terminology) a better choice. \$\endgroup\$ Commented Jun 14 at 9:07
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    \$\begingroup\$ doxin - Hi, Where did the image come from? To comply with the site rule on referencing, details of the original source of copied / adapted material must be provided by you, next to each item. If the original source is online (webpage, PDF, video etc.) please edit the answer & add its name & link (URL) (e.g. website name + webpage title + its URL). If the original source was a book or other offline material, please edit the question & add the best reference you can e.g. title, author(s), page, edition etc. TY \$\endgroup\$
    – SamGibson
    Commented Jun 14 at 10:49
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Use an appropriately sized twist-drill. Solder is pretty soft, so this is a really easy process, and can often be done with a bare drill-bit, held in the fingers.

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    \$\begingroup\$ Sounds like a perfect way to also damage the hole and maybe with some luck also introduce shorts to the middle layers... Always fun to trouble-shoot that. \$\endgroup\$
    – Lundin
    Commented Jun 14 at 14:22
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    \$\begingroup\$ Yeah this is not a good idea. While I've drilled boards to achieve some sort of modification, this is usually to destroy something within the board intentionally (like cut an internal trace). \$\endgroup\$
    – Steve
    Commented Jun 15 at 3:00
  • \$\begingroup\$ @lundin What middle layers? Unlikely to be any for the PCB described. How do you think the hole was made in the first place?? If you use a drill bit that is one or two sizes smaller than the hole (hence: "appropriately sized" then you won't do any damage, certainly I never have. \$\endgroup\$
    – MikeB
    Commented Jun 15 at 15:52
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    \$\begingroup\$ This is a viable method. The solder is soft and a sharp drill bit held in the fingers will let you feel if it is cutting solder or copper. \$\endgroup\$
    – KalleMP
    Commented Jun 16 at 15:14
  • \$\begingroup\$ @MikeB Most SMD PCBs are 4 layers or more these days. I think the hole was made in the first place before the plating was electroplated in place. And if you damage that plating, the plating itself could be causing the mentioned shorts. \$\endgroup\$
    – Lundin
    Commented Jun 17 at 6:42

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