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Because I tried to wire-solder a protoboard which failed miserable, I'm intending to order a PCB. However, to minimize the area, I want to use some SMD1206 components. I ordered some basic ones (resistors, capacitors etc).

However, now I read that for example SMD 1206 MLCC (Multi Layer Ceramic Capacitors) are very difficult to hand solder. e.g. here. That there is a need to preheat every component for 90-120 seconds and/or to use a heat gun.

I do not have a heat gun or other professional equipment.

My questions are:

  • Can I hand solder SMD 1206 resistors? (1/8 W and some 1/2 W)?
  • Can I hand solder SMD 1206 ferrite beads?
  • Can I hand solder SMD 1206 diodes/LED diodes?

Btw, my soldering skills are far from perfect.

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    \$\begingroup\$ 1206 is fine to solder with thin solder wire, tweezers, and a good iron. \$\endgroup\$ – Colin Jun 20 at 13:57
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    \$\begingroup\$ 1206 is no problem to solder by hand, 0805 and 0603 are easy. 0402 is harder, I can manage 0201 with an iron but it involves copious amounts of swearing. I would not standardise on 1206 because capacitors, ferrites and LEDs are becoming hard to obtain in that size. 0805 or 0603 are your best option. \$\endgroup\$ – Steve G Jun 20 at 14:07
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    \$\begingroup\$ 1206 is monster-sized. You should barely need tweezers. So help me, on first read I thought you were asking if a normal iron can pass enough heat to solder 1206's! \$\endgroup\$ – Scott Seidman Jun 20 at 14:18
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    \$\begingroup\$ I would just like to add: Make sure the first pad you tin is not one that connects to a ground plane or other heavy copper area. I have been burned (or, rather, my components and PCBs have been) by this several times before the light bulb turned on. \$\endgroup\$ – calcium3000 Jun 20 at 14:26
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    \$\begingroup\$ A trick I use when soldering really really small smd things is to use a hemostat (peang in Swedish, the more you know), they have the perfect shape (especially ones that are long) and perfect force to hold the darn small things in place. For those who don't know what it a hemostat is, it is a scissor-looking tool that has flat ends, if you press it together it holds something together and can only be released if you push the handle sideways. It is used in hospitals, specifically in surgery to hold certain things in place. \$\endgroup\$ – Harry Svensson Jun 20 at 14:29
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You will likely find that 1206 are actually quite easy to hand solder. When you get used to SMD boards, you will find they are actually quite large.

With a standard iron, I find it quite simple to hand solder 0603 components, and with a small precision iron, 0402 can be done.

Your best bet and my recommendation if you haven't don't it before is to pre-solder one of the pads, then heat up the solder with your iron, and place the component with tweezers. Once you are happy with the position, remove the iron then simply solder the other side. This is by far the best way if you aren't sure about your soldering skills.

If you have access to some flux, then make sure to use it!

If you want, you can make a PCB with a few different footprints on it, have a few 1206, a few 0805, some 0603 and so on, and use it as a 'practise board'. This way, you can develop your SMD soldering skills, and when you get more confident, you can switch to making PCBs with 0805 or 0603 components, as the larger sizes are getting harder to come by!

After @pipe pointed out the link in the question, I don't really have much to say on it. I have never ended up with a cracked capacitor or any component. The article seems to be talking about the heat shock of the component, and cracks occuring during the rapid heating and cooling of the component and the solder. By only soldering one side at a time, that should reduce these stresses anyway, the article seems to point to both sides being soldered very quickly, or at the same time. It also mentions that is can cause failures during a "board bending resistance test" which I assume is not needed in your application! So really, I wouldn't worry too much about it. If you do find on the off chance you have a broken capacitor, just replace it!

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    \$\begingroup\$ @MichelKeijzers they look small at first glance, but after you have had a bit of practise with SMD soldering, they aren't too difficult if you use the method I mention. Go for the 1206 for now, and perhaps make yourself a 'practise PCB' you can use as it'll be very cheap to get a few made in china! I have a few at home I use for some IC packages if I haven't done them for a while \$\endgroup\$ – MCG Jun 20 at 14:24
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    \$\begingroup\$ @MichelKeijzers Once you start, you won't look back! Chinese PCBs are so cheap now, and SMD components are usually cheaper than the through hole counterparts. The only real downside is the shipping time! And no, I wouldn't bother pre-heating. I never do. If you have one side connected to GND, pre-solder this pad first, then while the solder is still melted, place the component with tweezers. Once you are happy with the position, remove the iron, then solder the other side. Easy! As long as you have some flux to help you, I am sure you will find it quite a simple task :) \$\endgroup\$ – MCG Jun 20 at 14:30
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    \$\begingroup\$ @MichelKeijzers with good thermal relief, this shouldn't be a problem. I always solder this side first as it's the most difficult pad to heat up, and this way you guarantee a good connection with the component. It can be done either way, but that is just my personal preference. If you decide to make a practise board, you can always try sticking a ground plane on it and seeing what you find easiest \$\endgroup\$ – MCG Jun 20 at 14:37
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    \$\begingroup\$ @MichelKeijzers yeah, that should do it! Maybe on your test one you can add a few random components to test your soldering. As for the thermal reliefs, I answered a question about them a while back which should explain it: electronics.stackexchange.com/questions/439756/… \$\endgroup\$ – MCG Jun 20 at 14:42
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    \$\begingroup\$ Thanks for the answer (and read some more about it). I will add some 0603 'test footprints' to the test PCBs. \$\endgroup\$ – Michel Keijzers Jun 20 at 14:52
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I hate to contradict Murata; they are a solid company with good products and helpful documentation. However, I've been hand-soldering MLCC's for a decade and have never had a known MLCC failure. I don't preheat the board or components, and I'm not more careful with MLCCs than I am with any other SMD components.

I generally use a Weller WES51 soldering iron with an 0.031" conical tip. I've probably soldered a thousand components from 1206 (these are huge) to 0201 (I need a magnifier for these). Sizes down to 0603 are basic. 0402 is a pain. I'll only hand-solder 0201's if I have a really good reason :) These are imperial units.

Here's my technique, which seems to differ from others I see here. It's not necessarily better, but it works for me:

  1. Apply a small amount of solder to one of the two pads. Remove the iron.

    If I have a lot of components to solder, I usually prepare each location (one pad per component) in one pass. More time efficient :)

  2. Place a component on the pads. It will be resting with one connection on the lump of solder, and the other connection on a clean pad.

  3. Hold down the component with a toothpick.

  4. Touch the iron to the lump of solder. When it melts, the component will sink down to the level of the board. Remove the iron, then the toothpick.

    Note that this isn't a good solder joint yet! It just holds the component in place.

    I do this with each component before proceeding.

  5. Now that they're all tacked in place, I solder all of the unsoldered edges. This is straightforward; just use the iron and solder wire.

  6. Finally, I go back and retouch all of the original edges. This is critical, as some of them may have cold solder joints. Either add flux or just add a little more solder (for its flux).

So, basically, I tack them into place, then solder the other side, and then resolder the first side. It doesn't take long!

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  • \$\begingroup\$ Thanks for sharing your experiences, and your method of soldering I will try out (I have a Aoylue soldering station so it should be good enough for hobby projects), and 0 experience in SMD components so that will change :-). \$\endgroup\$ – Michel Keijzers Jun 20 at 22:07
  • \$\begingroup\$ I'm largely the same, but tend to do one part at a time instead of tacking them and finishing them all at once. Slower, but faster than finding the one component I forgot to finish! \$\endgroup\$ – Scott Seidman Jun 21 at 13:50
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1206 (Imperial, 3216 metric) is very easy to solder by hand.
It's very big in the SMD world.

With an normal, 0.5-1mm chisel, iron you can go down to 0603 (imperial, 1608 metric), then hot-air becomes a requirement to do it with reasonable quality.

The need for optical assistance depends on the operator.

Soldering with an iron is easy with these 3 steps.
1. Tin one pad, the other one must be clear.
2. Place component with tweezers while the pad is molten by the iron.
3. Solder other pad, this is where you need thin solder.

It is essential that you own at least lower or equal than 0.5mm solder with flux core. It is also important that the iron is not too hot, so you have some seconds before the flux is gone.

If you're pulling solder away with the iron (little spikes), you're out of flux. Add more.

It might work poorly with leadfree solder, add more paste flux in that case. (eg: SMD291)

With hot air, just tin both pads, add flux paste, drop component, and heat it. It will literally "flop" into place.

You can never add too much flux. Although it might smoke a bit. Just clean it afterwards and don't breathe the smoke.


Note that above method of soldering is not the recommended method by the manufacturer. It violates the thermal profile recommendations of the manufacturer, and might introduce physical stress on the parts due to uneven heating. This might not give you any failed parts immediately, but it might reduce the MTBF, and in the long term, or high volume, you may see higher failure rates then when correctly reflowed. Basically you work out of spec.
It's just like ESD, you may never observe cause and effect directly, but it's definitely a factor.

If your intention is to do this professionally, please invest in a hot-air station. It's worth it.
One trick when soldering with hot air is to use the surface tension of tin, it's amazing and does all the hard work for you.

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    \$\begingroup\$ @Michael you should include that information in your question. \$\endgroup\$ – The Photon Jun 20 at 14:20
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    \$\begingroup\$ EVERYONE who works on SMD boards should be using hot air. I thought it was some kind of crazy-hard skill until I bought a rework rig and started doing pick and place and paste and all the other things. Boards mostly come out looking professionally done, and that was with maybe 10 or 20 hours of practice. As you said, the parts just flop into place. \$\endgroup\$ – Julie in Austin Jun 21 at 1:30
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    \$\begingroup\$ @JulieinAustin Ehhh, I disagree mainly because you have to deal with solder paste storage and lifetime issues. It has it's place though. \$\endgroup\$ – DKNguyen Jun 21 at 19:15
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    \$\begingroup\$ @JulieinAustin -- works fine until you're reworking a densely populated board and parts go flying. Hot air is a tool like any other, and the right tool needs to be matched to the right job. \$\endgroup\$ – Scott Seidman Jun 21 at 19:35
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    \$\begingroup\$ @ScottSeidman - That’s just another piece of the “how to use hot air” skillset. Turn the air volume down and turn the heat up. If the part you’re working on is the small one, get a smaller tip. \$\endgroup\$ – Julie in Austin Jun 21 at 20:05
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Why wouldn't you be able to? I (and I am by no means special) can do everything up to 0603 (that is imperial, not metric) easily, and 0402 if I have to. Just get tweezers and you should be fine. It takes some trying the first time you do it, but once you get the hang of it it is easy.

There are these wizards (by which I mean our lab tech) who can even do 0201 by hand with a regular soldering iron but I don't even wanna think about how that is done.

Once I started using SMD for PCBs, I never went back to through-hole components apart from when I have to. It is so much neater and easier to do SMD once you get the hang of it...

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The way I see it.

A modern high end PCB can contain literally hundreds of MLCCs, a single field failure can doom the whole PCB to the e-waste. So for production use the reliability of the capacitors needs to be extremely high.

If you want to maintain those extremely high levels of reliability with hand soldering you probably do need to take precautions that go beyond what most people would consider reasonable.

But frankly you usually don't need to, only a masochist would be hand-soldering hundreds of SMT capacitors onto a product they are mass-producing. In the hobby/proof of concept/prototyping world MLCCs hand-soldered without special precautions are IMO unlikely to be a significant contributor to your overall failure rate even if they do have a much higher failure rate than reflow soldered ones.

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  • \$\begingroup\$ Do hot tweezers count as hand soldering? \$\endgroup\$ – DKNguyen Jun 20 at 18:43
  • \$\begingroup\$ IMO yes (though i've never found them much use for soldering, I regard them mainly as a desoldering tool) \$\endgroup\$ – Peter Green Jun 20 at 18:52
  • \$\begingroup\$ Thanks for this answer ... and yes, I hope I only have to make one, or in general, when I make more (different PCBs), there will be on average a few or max 5 or so on each PCB, one per IC. \$\endgroup\$ – Michel Keijzers Jun 20 at 22:03
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If you are like me, your hands are just not steady enough to position the component and solder it at the same time.

My method is certainly not a production soldering technique, but I like to use a toothpick to place a tiny drop of glue between the two solder pads and then plop the component on top. I have a few minutes to gently nudge the component into the best position. After a couple hours my old eyes and hands are then able to solder the component with no trouble.

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    \$\begingroup\$ For that kind of board work, I use tack flux instead of “regular” flux. The other “trick” is to tin the pads, then a little flux on both pads, and re-heat. If you hold the part down with fine-tipped tweezers you’ll keep the free end close enough to the tinned pad that capillary action will wick the solder up and onto the other end of the component. The key, however, is flux as it will help prevent oxides and a bad joint. \$\endgroup\$ – Julie in Austin Jun 21 at 1:26
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    \$\begingroup\$ @JulieinAustin Thanks for the tip, but it is the "hold the part down with fine-tipped tweezers" that is physically difficult for me. My brain knows what should happen but my hands don't always cooperate. \$\endgroup\$ – Elliot Alderson Jun 21 at 11:26
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    \$\begingroup\$ It's a skill, that's for sure. I started soldering 45 years ago, so I have a LOT of practice with an iron. If it's just practice, practice more. If it's something else, well, there are ways around a lot of problems. One thing I've learned when doing fine board work is to watch my breathing, and my coffee intake. \$\endgroup\$ – Julie in Austin Jun 21 at 13:34
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    \$\begingroup\$ fully agree with the coffee intake, after the 3rd cup things start getting ugly. \$\endgroup\$ – Tyler Stone Jun 21 at 23:05
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For me it's possible, but I think it is also feasible for you to do it by hand. The easiest way is to first put tin on the pads. then you can grasp the component with tweezers, warm the pad and then press the component on it. And also use solder flux ;).

here you can find a video how to do it.

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