Just curious how many people on here have tried their hand at home brew SMD soldering/reflow. If so, any pearls of wisdom they’d like to share?
Well have done some work with SMD components here is my advise.
- Start with the bigger SMD components first and build your confidence
and skill. - Get a decent temp controlled soldering iron.
- Don’t drink a lot of coffee on an empty stomach and then try and mount them, this will lead to the smell of burning flesh and a lot of involuntary swearing. Which reminds me that it takes a very special and strong-minded kind of atheist to run to the basin to pour cold water over their burnt fingers and shout, “Oh, random-fluctuations-in-the-space-time-continuum!” or "Aaargh, primitive-and-outmoded-concept on a crutch!”
Other than that it is not that hard just a little bit of practice and you should be fine.
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I like it, duly noted!
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I’ve been SMD soldering for 6 years now. Honestly I think it’s much better and yields nicer looking boards than through hole.
- Get a decent set of tweezers. Non-magentic is especially important to ensure components can be placed easily and accurately.
- Use flux. The more the better. (So long as it’s cleaned off after soldering)
If you are finding it hard to physically solder the SMD parts, find some e-waste and practice. This is how I started, Removing components, then try re-soldering them.
Start designing your boards with SMD compoents, start large 1206 or 0805. To aid in soldering most CAD software should allow you to increase the SMD pad length. (A handsoldering footprint variant, Some packages call this low-density).
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+1 for avoiding coffee!
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Not sure if this is obvious, but in addition to everything that’s already been said, I can suggest buying a second soldering iron (it doesn’t have to be good quality) as this will help you take off SMD passives that you put in the wrong spot. Hitting the erroneous part from both sides with a soldering iron in each hand is the easiest way to remove them (IMO).
When it comes to taking off ICs or transistors (i.e. components with > 2 pads), you’ll probably have to invest in a hot air gun :-).
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Like a lot of others, I also prefer working with SMD components. Apart from being able to create nice and compact boards, there’s the general challenge and satisfaction of working with modern technology.
Just thought I’d throw in a few other tips:
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Get some fine solder, no more than 0.5 mm in diameter. It will give you much better control over how much solder you apply.
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Solder wick is your best friend. You can solder really fine pitch ICs by dragging a blob of solder along the pins and then cleaning up with the solder wick. Don’t worry, you’ll never be able to suck the solder out from between the component and the pad!
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Avoid the temptation to go for a really fine conical tip for the iron. You’ll find it hard to transfer enough heat to the pin.
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If you do need to remove a component, often the easiest way is to add a lot more solder. It’ll stay molten long enough for you to be able to heat up all the pins and gently remove the component.
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The easiest way to solder an SMD component is to put a blob of solder on one pad, place the component and tack it down with the iron. once you’re happy with the placement, you can solder the rest of the pins.
I bought some solder paste once and tried the hot air approach. I think it’s only really worth it if you’re going to make multiple boards and use a stencil to apply the paste (and a reflow oven).
Well I’m about to go the hot air method on a power supply project I’m doing. Hopefully it’s a win.