SparkFun According to Pete #45 - SMD Soldering Tips and Tricks
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- เผยแพร่เมื่อ 2 มิ.ย. 2024
- On this very special edition of According to Pete, our intrepid DoE is sharing some of his favorite and most useful SMD soldering tips - because no Training Montage ever started with the hero already being really good at soldering.
6:48 how to rip pads by being impatient: My biggest tip with solder wick - always remove it WITH the soldering iron tip, this way it's always hot, and you don't risk it sticking and ripping up pads. Also, avoid moving the wick over the pads - put it down squarely, and pull it up with the iron again. So much less chance of ripping pads.
Cool box of tricks! If I may add three more:
1) If you need to take off an IC without cutting the leads, add a resistor-lead (or a thicker diode-lead) as a bridge and heat-tank across each side of the IC, with a glob of solder. You can heat each side in turn till both are molten and the IC slides off.
2) The (steel) blade of your knife is not easily wettable by solder. If yo need to remove solder-bridges, the area can be melted and the knife inserted in between the molten solder (like T1000 going through the steel bars) to get rid of the bridge. Flux helps the separated parts to bead up nicely.
3) After soldering 2-pin SMDs (like the chip-resistor) you can use the iron to melt both ends simultaneously. Surface-tension holds the chip in place, and the device "auto-adjusts" to a flat orientation neatly centered on the pads.
Cheers!
Surface tension only applies when you are not touching the part. He was. Loved your T1000 analogy!
While that is true, the surface area of pads is usually larger than the contact-area of the tip of the soldering iron. In the tug-of-war that ensues, the pads 'win' and the SMD-component stays on the pads (for me at least) - then the (still molten) solder allows the device to settle nicely on the pads. Every once in a while, the component may cling to the iron, then its a matter of wriggle and squirm. (Or use a hot-air pencil)
I've bought a cheap chinese reflow oven (well known T-962), "fixed" it by flashing open source firmware and some minimal hardware changes, and since that I rarely solder anything manually (except for TH parts of course). It was like $200, and "fixes" took about 2 hrs of time and about $3 in parts (a MOSFET and a one-wire temperature sensor).
Now I'm using mostly 0402 passives since they are dirt cheap ($10-30 for the reel of 10000 elements which will last forever and some more time after that), and using larger parts only when I know I will have to manually remove/replace (these are mostly 0 Ohm "jumper" resistors), or when 0402 versions just don't exist or too expensive (these are mostly capacitors of large capacitance). In the beginning I was worries these will be too small to handle,. but a headset with magnifying lenses and integrated LED light proved to be more than enough. As a bonus, my boards have become significantly smaller. As a side effect, I can now use LGA and BGA parts without any problems (previously I had to use hot air to solder some really small sensor ICs).
So I would totally recommend investing in oven if you're serious enough about soldering.
Pete.
My hero dude. I am just about to start my first SMD project and this helped a great deal. Cheers
A rare and great video on point to point wiring, thanks.
Cutting SMT leads with an x-acto knife can put enough stress on a pads to cause one to lift. Also, a lead end could easily get snagged or stuck to the solder wick and rip a pad while removing them from the pads. I would suggest reflowing and lifting leads one at a time until you get down to about 3 left. Then reflow the last 3 and lift off the IC. It consumes more time, but is much safer for the PCB.
Is there any reason the US pronunciation of "solder" is "sodder"?> I've noticed it consistently in US tutorial videos. But apart from that nitpick, about which no-one can do anything, great video Pete; appreciated the tips and the sense of humour.
This was a great video, learned a lot. Thanks!
Thanks Pete, great video. Appreciated.
ChipQuik, as +EricWertz says below. Low-temp solder that stays molten for quite a few seconds to enable single-iron removal of parts. A tweezer iron, of course, is awesome for a lot of different kinds of parts, as is a hot-air rework station with different nozzles. We have both of those here at work, but I can get a lot done with ChipQuik, a heat gun, and a flux pen. Another trick for SMT two-terminal packages (Rs, Cs, Ls) is to wick the solder off one side and slip a small #11 Xacto knife under that side while heating the knife and solder with the iron. Then wet the other side, and off it comes.
You should always use the solderwick parallel to the direction of the pads. Cleaning them up perpendicularly (when you can clean all the pads in one sweep) is a pretty good way of ripping out the pads if you're not using solder that melts easily/low copper weight PCB. It might just ruin your precious chinese fab PCB that you waited so long to get.
On another note, would be really cool to see a video about energy harvesting. You already used the dickson charge pump, why not use it to buff up some wireless signals to power a low power circuit? Would be interesting to see the process behind that ! I've been doing some things with wireless energy harvesting but only with NFC where you just calculate the antenna inductance and boom, it works. I never quite got antennas and would be really cool to see some videos about it. Maybe one or two videos about how to calculate and build an antenna, communicating with it using a couple of arduinos and then move on to the energy harvesting video so it doesn't get too much for one vid !
BTW: This is According to pete #44 ? the #43 was about charge pumps :p I love your videos, keep em comming !
Thanks for the video! Would love to see more soldering videos! And, is there any reason why you don't use a fume extractor?
Thanks Pete. This is great.
You should teach people to USE ADDITIONAL LIQUID FLUX.
It makes a huge difference especially with surface mounted components.
and ps. most of the techniques shown on video only work if the pads are long enough to be able to put solder and a big iron tip. When the pads are almost only as long as the leads, you wet the leadss and the pads with liquid flux, switch to a tip that has a tiny depression which allows you to "fill it" with some solder (the flux in the solder will evaporate, that's why you need separate liquid flux) and then just slide the solder over the leads and the solder will wick on the pads and leads.
*****
There are such tips for Hakko FX soldering station used in the video, and they're reasonably priced, at less than 20$ for genuine tips, just find the right distributor/store to buy them from. See for example Hakko T18-S7 or Hakko T18-C4, both are great for the method I mentioned.
You can also buy sets of 10+ FAKE Hakko iron tips from eBay for 10$ or something like that, the pack would include tips that work well for drag soldering. They're fake, they don't last as long, the temperature control is not as good as with genuine tips, but they're less than 1$ each so sometimes they're worth it.
I also bought a used Pace HW-50 off eBay for around $80, new models from Pace that use the same tips cost around 200-300$. The tips have the heating element built in so they're a bit more expensive, but I can still buy them from electronics distributors like Farnell for less than $15 each.
If you don't believe me, jus go on farnell.com or newark.com - same company - and enter 1124-0035-P1 or 1124-0034-P1 in the search box.
So sorry, it's not stupid money, lack of money is no excuse to limit yourself to chisel or conical tips.
Look into using a Zephyrtronics preheater like the ZT-1 AIRBATH, ANALOG and low melt solder - Desolder at 150c! You can lift a qfn with a ground flag off the board with ease. Also it is ideal for plcc tqfp etc!
Very helpful, thanks a lot
Good tips. I like this video.
Liquid flux is good to make sure the solder flows well.
Greaat vid Pete, but how about showing us how you do one of those sm caps that were in the frame of almost every shot. I have futzed with these and have never been happy with the result. Thanks.
Thanks for another according to Pete!! I've never seen solder wick pulled from pad to pad like that before, neat! Maybe that's why it never works for me :D
Just getting back into soldering. My trouble is header pins sticking up through holes, for shields on Raspberry pi.
What temp do you run your iron?
Always let people know that if they can't get the parts off that there is a chance that it is lead free solder that requires more heat to remove.
Also, get a smaller tip or at least a knife edge tip :)
Do you have any of the model Heico iron shown? I don't like the digital version.
Much easier if you apply flux first before soldering it keeps pins from bridging.
Can someone help me here, when ever I solder smd led, while soldering the led lights up and the magic smoke comes killing the led.
Make sure its an ESD safe tip
What temperature are you using on your iron?
Ya know... I'm not exactly sure. I turn it up until solder melts, then I notch it up some so everything flows fast. I'm generally a fan of more heat.
360'C or hotter with a fat tip. The high temp allows you to finish the job quickly, thus (counter-intuitively) a hotter tip allows for smaller heat-injection into the device I'm soldering.
Thanks, both. That's exactly what I was wondering--didn't want to damage nearby components.
Your tip should be hot enough and have sufficient heat capacity to reflow solder within a few tenths of a second upon contact.
5:53 Hmmm... "clown chasing hat around a ring" ??? ;)
7:19 By adding additional flux the solder Braid/Wick will more easily remove the solder bridges. I hate using metal tools on PCBs to remove solder bridges.
BTW using standard rubbing alcohol (99%) you can remove excess flux from the solder repair.
i came hear to learn about soldering tips but you didn't mention what soldering tip i should use.
Isnt English just beautiful :0
Looks so easy in the video ;( tell that to my fried PCBs and damaged pads;((
why promote leaded solder? I use unleaded and works fine for me.
My electronics area is pedals and tube amps. Uhh, without leaded solder tube amps are much less reliable! The heat and Sonic vibrations make connections fail. Unleaded is brittle.
People who complain about leaded solder should never drink Alcohol. There is way more risk in drinking alcohol than using leaded solder.
There are still a lot of houses and buildings that have copper water lines soldered with 50/50 Lead Solder.... Just got done remodeling an apartment complex and found a empty roll of 50/50 Lead Solder in the walls.
video should be called "how to do SMD soldering like an amateur"
what's missing?
The position I was trying to solder from wasn't really great, so yeah, the work you're seeing is sub par by my reckoning. The methods are sound, though... well, they are for me.
yes! This seemed like a helpful video to me. Thanks for putting it together.
That was pretty sloppy soldering! It would never meet any inspection or quality requirements. How about some aids for the ol' peepers? You're just showing off your young eyes. Other than that, well done. Oh, and buy some flux.