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I recently bought this product. I would like to know what the best way to solder something such as a wire to those metal leads. Any suggestions?

The board


marked as duplicate by placeholder, Passerby, Kaz, Anindo Ghosh, Olin Lathrop Apr 23 '13 at 12:06

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    \$\begingroup\$ In the interest of avoiding clutter I'm going to recommend a close to this question. Not that it isn't worthwhile, but that there are many similar question here already with good answers. \$\endgroup\$ – placeholder Apr 23 '13 at 0:27
  • \$\begingroup\$ Agree with @rawbrawb There is nothing special about this 0.05" (Soic Pitch) part or soldering needs besides: Tin, Use Flux, Use appropriate sized small gauge wire. \$\endgroup\$ – Passerby Apr 23 '13 at 0:45
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    \$\begingroup\$ @rawbrawb I think this is actually a unique question if the answers focus more on the lines of "Prototyping with a PCB with Castellated Holes". \$\endgroup\$ – justing Apr 23 '13 at 3:09
  • \$\begingroup\$ @rawbrawb, I kind of agree with you, but I definitely don't think it is a duplicate of the "soldering techniques" question that you mentioned. I'm sure there is a similar post about soldering out there, but it's just as easy to answer this one as it is to search for a true duplicate. \$\endgroup\$ – Kurt E. Clothier Apr 23 '13 at 4:43
  • \$\begingroup\$ I agree with @justing. This is a specific question that is not addressed in the 'duplicate' question. Voting to reopen. \$\endgroup\$ – user17592 Apr 23 '13 at 16:18

If you have any flux you should first add that to the pad, but this isn't entirely necessary.

Add a small bit of solder to the metal pads, then lightly coat tip of the wire with solder as well.

Next, place the wire up against the pad and heat the wire and and pad with the iron. As soon as the solder melts, push the wire completely against the pad so it is making a solid connection. Remove the heat, and hold the wire in place until the solder hardens.

Things to remember:

  • It is important that wire is completely up against the pad and not making the connection through the solder alone.
  • Don't keep the soldering iron up against the pads for too long as it could overheat and damage the components already on the board.
  • The solder is holding the wire(s) in place, but you can add something like hot glue over top of the connection to prevent the wires from pulling away too easily.
  • Use a continuity tester to check the connections of each wire to pad and ensure you did not short any pads together.
  • As stated by Kaz, using a set of helping hands is a good idea. It can hold the wire to the pad, allowing the solder to harden completely undisturbed.
  • \$\begingroup\$ The metal pads are quite tiny, and I am afraid of if the solder gets heated it will spread out and connect to the other metal pads next to it \$\endgroup\$ – user151324 Apr 23 '13 at 12:08
  • \$\begingroup\$ For that, I would refer you to the other questions about soldering techniques: electronics.stackexchange.com/questions/1388/… You want to use very little solder, and do not "drop" it on the board. Tin the tip of the iron first - you might even be able to coat the pad just with the a small blob on the tip of the iron. You have two choices: try to solder it, or be scared and let the thing sit uselessly in a pile somewhere. \$\endgroup\$ – Kurt E. Clothier Apr 23 '13 at 18:19

Get a helping hand. This will hold the board, and the wire to the pad. You just apply heat and solder.


I don't think there really is a 'best' way. So long as you can do it, is the best way.

What you can do is put some solder on the pad, and while its still molten, stick your wire in the molten solder. Do a continuity check as you go, or at the very end to make sure that you have a good connection between your wire and the pad.

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    \$\begingroup\$ Just placing a component in still liquid solder is a pretty unreliable way to solder. The component also needs to be hot or else you run a very high risk of a dry solder joint. This is pretty much the classic no-no if you ask me. \$\endgroup\$ – NickHalden Apr 23 '13 at 0:48
  • \$\begingroup\$ OP asked how to solder a wire. That is a way. Its not, stick it in, and let go. OP didn't specify that that he's never soldered before, and has some perhaps through hole experience. He's obviously never had experience with these types of pads and putting solder on , and soldering the pad and placing a wire in it (since the iron is still on the pad), is fine because it will also heat the wire. I also tell him to check his join with a continuity check. kthxbai. \$\endgroup\$ – efox29 Apr 23 '13 at 1:36
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    \$\begingroup\$ A simple continuity check won't necessarily tell you if you have a good solder joint -- even a poor cold solder joint may show good continuity at first, but it's mechanically weak, so vibration or mechanical stress on the joint can break the joint. \$\endgroup\$ – Johnny Apr 23 '13 at 2:52
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    \$\begingroup\$ @efox29 I didn't mean my comment as a personal affront, so there's no need for the snarky "kthxbai." The OP says absolutely nothing about his/her prior soldering experience, so it would be a terrible idea to assume he knows something and therefore leave very incomplete instructions. Furthermore, even if you leave the iron on the pad that says little to nothing about the temperature of the wire which is the main problem with your answer to begin with. The iron should be touching both the pad and the wire simultaneously. \$\endgroup\$ – NickHalden Apr 23 '13 at 3:25
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    \$\begingroup\$ @efox29 - Just for clarification, "kthxbai" is a pretty smartellic sounding thing to say, regardless of the intentions of the the phrase. It is reminiscent of "talk to the hand" or a responsive "whatever." I would refrain from saying things like that to avoid needless confrontation. \$\endgroup\$ – Kurt E. Clothier Apr 23 '13 at 4:40

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