SDG

$2 for PCB Prototype(Any Color): jlcpcb.com/
1. Yellow Solder Paste: bit.ly/2Yhd9rg
2. Mechanic MCN-UV80: bit.ly/2XyaqwM
3. Pro'sKit 8S005: bit.ly/2J7FDO2
4. Weller F-SW21: bit.ly/2Yg0k0B
5. AG Termopasty TK83: bit.ly/2ZOnOdr
6. AG Termopasty LP-1: bit.ly/2J7H6UD
7. CIF F42202 Gel Flux: bit.ly/2Yk47de
8. MG Chemicals No Clean Gel: amzn.to/2IQ1j25
9. Best BST-223-UV80: bit.ly/2X4gbhe
10. Relife RL-421-OR: bit.ly/2XC6sDd
11. Relife RL-422-IM: bit.ly/2IRsU33
12. Topnik Zel Flux: bit.ly/2X8bUcV
13. KSS S800 Flux: bit.ly/2JdHlgT
14. Amtech NC-559-V2-TF: bit.ly/2XbakvI
15. Fake Amtech NC-559-ASM: bit.ly/2KGhL7u
16. Kester No Clean: bit.ly/2KDRA15
Equipment:
T12 Soldering Station: www.banggood.c...
AC Version: www.banggood.c...
T12 Iron Tips: www.banggood.c...
Daniu Tip Cleaner: bit.ly/31VHwWM
KSGER T12-BCM3 Tip: bit.ly/2xgYXCQ
Amscope Microscope Head (US): amzn.to/2YmZWNx
Amscope Trinocular Microscope (US): amzn.to/2YdBE8k
Amscope Trinocular Microscope (UK): amzn.to/2V8w9Gh
Swift SS41-WF20 Binocular Microscope US: amzn.to/2VLWEpb
Swift SS41-WF20 Binocular Microscope UK: amzn.to/2GYGYFV
Support the channel: / sdgelectronics
Visit my website: www.sdgelectro... #ElectronicsCreators

[@jamesdavies686]

I realize it's only been a little over a year, but you should do this same video again as a revisit with some same and some new brands. Since bait and switch happens so often in the parts world, would be interesting to see if the cheap stuff still holds up today.

[@cerglabs3646]

Excellent suggestion.

[@fmburner]

Should throw kingbo in the mix

[@FranckBossi]

2 years now

[@3nertia]

I would like to second this ...

[@hoggif]

Banggood yellow tub melts at (or below) 100C. I melted it and poured in syringes. Quite cheap and seems to work well. You get quite a few syringes out of a tub of that!

[@g4z-kb7ct]

I have some of the same stuff and here in Australia it gets quite warm in summer. I had the tub sitting on its side and one day I noticed the flux had leaked out. So it melts or at least softens enough to flow at a lot less than 100. More like 35-40. Anyway, this isn't proper flux and does not have any active component so it's pretty useless for reworking old parts.

[@light_creations]

Yellow Solder Paste: 4:09 Mechanic MCN-UV80: 4:38 Pro'sKit 8S005: 5:11 Weller F-SW21: 5:42 AG Termopasty TK83: 6:06 AG Termopasty LP-1: 6:39 CIF F42202 Gel Flux: 7:04 MG Chemicals No Clean Gel: 7:24 Best BST-223-UV80: 7:44 Relife RL-421-OR: 8:08 Relife RL-422-IM: 8:32 Topnik Zel Flux: 8:53 KSS S800 Flux: 9:13 Amtech NC-559-V2-TF: 9:31 Fake Amtech NC-559-ASM: 9:48 Kester No Clean: 10:06

[@requiem4adreamc]

Thanks a lot

[@rangwankasantikul9223]

I guess it might be a great idea to rerun the tests on a non-plated copper boards. That's a better way to test the flux's ability to deal with oxides.

[@goodun2974]

Yeah, soldering brand new circuit boards with gold plated pads to brand new integrated circuits with shiny pins is a very easy test. In the real world people have to solder components and wires to oxidized terminals of switches and pots, old turret boards, and so on.

[@electronicsoverhaul]

Chip Quik SMD291 is great for soldering on ICs. It has a low viscosity, a greasy consistency. SMD4300TF10 is good for whatever else. Amtech does leave a sticky residue I don't like. When you heat the flux, it’s very transparent making it easy to see what you're doing. These are good for phones and small SMD work. I think rosin-based flux is fine for just about everything but can be harder to see for the small stuff with it's yellow coloring or becoming browner with heat. Rosin doesn't evaporate and smoke as quickly as Amtech. You can heat rosin to 500C, and it won't evaporate. It can turn darker as it heats up with use as you slide the solder iron around it more. Use what you like for whatever applications.

[@Galactus314]

These fluxes were all tested on surface mount components, using PCBs with no vias. When heated, they all turn to liquid, and near by vias could drain it away. The liquid fluxes you can clearly see evaporating along the right edge at 6:20 and 6:50 respectively. They seems to have very limited uses. As someone else commented, I'm curious how the SRA No Clean Tacky Flux could handle those condtions. Also, I do a fair amount of through-hole soldering, and literally all of these fluxes are simply too thin for that. So I'm seeing a good case for another video. Boards with vias, the SRA flux, and something for the THT crowd (zinc chloride, as well as non-ZCl). Thanks!

[@goodun2974]

I'm curious if you're using a Aoyue soldering/desoldering station from SRA; I used an INT701A++ dual station at work for my last 5 years prior to retirement because the 1980's Hakko desoldering stations we had all died and we couldn't easily get parts. I was thinking of buying one of the Aoyue desoldering-only stations from SRA to use on projects around the house. They're only about 140 bucks as I recall. The 701 a worked surprisingly well for me as a full-time audio-equipment bench repair tech, although I did a couple of tweaks and mods to the guns to make them work a little better without clogging.

[@What_I_Make]

Your analogy on the fluid is spot on. As a part of the soldering I carried out at work, we looked at this and using the microscope could see the heat from the soldering iron directly burning off or evaporating the adjacent flux. I do have a concern with the thin consistency. Originally and at home, I use a thick paste and found, and in both cases, they last a very long time. With the thinner paste, it is tough to administer by hand, and because the density is lower gets used up very quickly. This may be my method, but there was a definite consumption at work between the two.

[@KimoKimochii]

by the flux lasting long does it become so thick it’s unusable? i find after a few minutes the flux gets so dried and thick on the board i need it clean it off and reapply

[@g4z-kb7ct]

Another point to mention is most if not all smd fluxes need a proper reflow process heat curve to become inactive. Soldering by hand does not make this type of flux inactive which means it'll remain slightly acidic and will eventually eat the copper traces. An easy way to fix this issue if soldering by hand is desired is to use hot air afterwards, just enough to heat the area to activate the flux so it goes hard then you know it's inactive.

[@trevorwhite9138]

Thanks, this was a really useful video. Having all the links really helped me find the best product and the easiest for me to order.

[@TheGuitologist]

Excellent comparison. Very helpful.

[@allallall2321]

HUITA

[@fraserhardmetal7143]

Very expensive for what you get - just make your own - you can buy a kilo of rosin for less than one of these fluxes. Mix rosin ( flakes preferably ) with vaseline ( anything from 1:0.5 - 1:2 ) or however runny you want to make it. Don't forget it is the rosin that does the job here, despite what other proprietary ingredients are in the commercial stuff. Put in a glass jar , mix, and heat gently in the oven until the vaseline and rosin separate - remove from heat , remix and heat again. Remove from heat and allow to cool. When cooled enough to still be liquid, the mixture can be drawn into syringes - at this point you can add some 99% isopropyl alcohol to the mix ( 1 - 2% ) to aid fluidity, but really it is up to personal preference - experiment with the recipe, it's not set in stone, the more rosin that's in it the better. The acid in the rosin should be enough for regular soldering - badly oxidised components would probably require something more acidic - try adding some citric or malic acid - it's up to you. Remember to vent fumes - at least you know what's in your homebrew flux - goodness knows what's in the Chinese knock- off stuff.

[@rogierius]

I like this! Thank you.

[@marcotestarmata]

IMHO the genuine Amtech really shine when used with an hot air gun. It really make the difference, it stays there active for a long time but you really need good ventilation or a real fume extractor, it is very smoky. The fake Amtech's residue are much harder to remove and they spread wider on the board. It is cheap but i won't buy it again. For general soldering i like to use the liquid TOPNIK RF800 in a squeeze bottle with a fine gauge needle. I work mostly with beefy through hole components. RF800's residue are really easy to remove with IPA and the flux works very well and it is not very smoky. Liquid flux are good just with a soldering iron. With hot air you need a gel flux, and the Amtech is the the best flux i've ever used. Just my two cents.

[@sdgelectronics]

I'm going to do a test with hot air shortly - firstly with the PCB used in this video, but it sounds like it would be worth getting another test board with some large ICs and a ground plane on it. Thanks

[@Slavolko]

Louis Rossmann swears by genuine Amtech flux for all the work he does. In fact, he buys and re-sells them because he trusts them that much and wants others to be able to reliably source the genuine parts.

[@pr0xZen]

@@Slavolko It's fair to promote it as it's genuinely great for its appropriate usecases. But its also really expensive, at least for those who do not generate any revenue on soldering work. And for many of those without a national/regional distributor, as international shipping and potential import taxes can make the total price really brutal. I need to point out that the sentiment pushed by Louis about the _process of buying_ Amtech flux is a horrible ordeal involving faxing orders etc, is either false or long outdated. You can just order it online from Amtechdirect.com . They're one of the few official distributors for Iventec (Amtech is a product lineup, Iventec is the company), and as such they keep shipment-ready stock of pretty much the whole Amtech lineup. So if you need _anything else_ from the Amtech lineup, these guys are great to have around, as you don't need to worry about getting fake products. That said - unless you want 10cc quanitites, or large tubs, buying no clean 559V2 tacky flux from Rossmanngroup is not a bad idea at all if the shipping etc works for you. Because the 30cc units Rossmann Group sell, are $16. From Amtechdirect they're $27.

[@MPETE1976]

Good to see RF800 being recommended as I have a 100ml and 2x50ml bottles + some other stuff coming my way from Poland this week.

[@MPETE1976]

@@pr0xZen $34.99

[@ristomatti]

I'm just starting with SMD soldering (or planning to do so for long) and this was extremely useful information. The brand/price overlays over the different options and again on the results was brilliant. So easy to compare. Talking pace and speech clarity also spot on. Great work, thank you! Two things I would have liked to hear (or missed): 1) what type of solder was used, 2) is the shelf life of the flux jars longer than on the ones that come in a tube? With the little time I have, it might be weeks or a month between I solder anything requiring flux. It's quite frustrating as the manufacturers state the shelf life to be only months. I've seen tips of reactivating old flux with IPA (maybe it was also on your channel?) but I've yet to try it.

[@paulgrodkowski3412]

Yes, Italian's are goog engieers!

[@ristomatti]

How is this related to my comment 3 years back? My questions are still valid btw. I've yet to have the time (or need) to get into SMD. 😬

[@paulgrodkowski3412]

@@ristomatti My apologies.

[@goodun2974]

​@@ristomatti, perhaps this will begin to answer one of your questions: I have a small plastic tub of Weller flux, ingredients stated as "a blend of rosin and petroleum jelly", that is about 40 years old and still works fine despite having tiny crystals on its surface. I don't know if this type of longevity will apply to the modern fluxes of today, but it appears that rosin itself is stable and inert, and the only thing likely to degrade is the chemical jelly or petroleum type product that the rosin is presumably mixed with. Perhaps the short lifespan stated by some flux manufacturers is a get out of jail card for them when they sell flux for critical applications such as the military. And like you, I don't work with surface mount components; I work primarily on single-sided circuit boards in vintage audio gear, and older point-to-point tube amplifiers or those with turret boards and eyelet boards. I don't work with brand-new SMD components and PCB's.

[@ristomatti]

@@goodun2974 Thanks for this. My comment was "a bit" long ago, and my electronics hobby has been on hold almost the same time. But I'll go continue keeping l the small jars in the fridge "for that one day" 🥲

[@ivanr5315]

Although an old video, it is really useful. I used to use the amtech fake flux for years and recently tried the CIF. The CIF leaves a sticky residue that in my opinion needs to be cleaned. Fortunately it is easy to clean.

[@AlexandreKandalintsev]

I disagree in two ways :). First, for new shiny parts flux performance doesn't really matter. Second, there is an important part of test is missing: test for electrical conductivity and acidity. Flux, by the nature, is acid. The stronger acid is, the better is soldering. So, top-performant fluxes are almost always have to be cleaned, even if they are "no clean". "No clean" is actually misleading, as what it means is flux, if _properly activated_ in reflow process, may be left on the board. This doesn't include hand soldering. Without cleaning most "good" fluxes cause corrosion and ruin performance of precision circuits (ADC, DAC, amplifiers, etc). Even with a proper cleaning agent it's not always easy manually clean the board, only ultrasonic baths can get underneath of ICs, etc. Because of this, I always recommend using _mild fluxes_ that can actually be left on the board without impairing performance. So, what I recommend is do so-called SIR-test on fluxes. I'm pretty sure you'll get surprising results.

[@unodos1821]

Hay you know Mr. Carlson lab?

[@sdgelectronics]

I'll look into this, thanks for the insights.

[@TheEmbeddedHobbyist]

I don't use flux unless its in the solder, cleanliness is your friend and you don't need to buy it. don't handle your PCB's too much, keep components in sealed packets for as long as possible. handle as little as possible. keep blu-tack for sticking things to the wall.

[@invendelirium]

I use water-soluble fluxes, they are easy to clean. Be careful not to use solder with rosin-based flux in them - that's quite a limitation, the vast majority are rosin-core. Solders with water-soluble flux do exist, but they are very rare. Using flux-less solder isn't quite as convenient.

[@trif55]

which kind of mild flux would you recommend for hobby electronics? I have rosin core solder already but sometimes a little extra flux would really help neaten things up

[@fishyrider3528]

Point to point old radio oxidized joints. Need the test. Great job. Good to have you back. Hello from Romania.

[@dvmavgoor]

Zinc chloride containing fluxes (such as the weller one) are not suitable for electronic components soldering, they are mostly for plumbing since ZnCl2 is pretty corosive and has to be removed after soldering. Moreover, ZnCl2 is extremely dangerous for a human: it's a skin irritant and its fumes cause lungs diseases.

[@sdgelectronics]

Interesting, I hadn't noticed the composition but it was picked out alongside the other flux pastes from an electronics supplier.

[@joepangit6938]

The yellow tub of Bangood flux is really nice, and can ship from USA. The only down side to it, is that a brand new one weighs 113 grams including the container. So it's maybe 100g, not the 150g they sell it as.

[@DevilbyMoonlight]

I may be showing my age but I still prefer using solid pure rosin and dip the tip in that when needed, it is amber coloured and glasslike in appearance, if I need a liquid form I just crush a small piece and disolve it in alcohol - its worked well for me for over 30 years,

[@Zellonous]

the great thing about tubs is being able to dip wires into them for wire tinning, etc.

[@SaccoBelmonte]

I love this comparison. With one video you just demonstrated almost all flux products work fine (except the liquid ones I think).

[@tomvleeuwen]

I would be interested in how good these fluxes perform when using hot air soldering.

[@Kholaslittlespot1]

Yeah, this is when the liquid fluxes should come into their own

[@rhalfik]

I use topnik mostly because it's a local brand, but I can tell that gel works better than liquids. They have their use for sure, but they're displaced too quickly with heat. Gel is more persistent. It's also easy to wash away and I don't get the problem with lumps, although I find a small brush useful as with any flux.

[@linkavichtruousky1]

I have previously bought inexpensive Chinese flux and after using it even in a well ventilated area would feel a bit sick sort of like flu symptoms. After switching to a name product i dont get this anymore so be careful as i have no idea whats in the cheap stuff and I’m sure there is not much quality control happening. The cheap flux cost me $1 AU compared to $15 AU for a rosin flux that i use now.

[@tristankordek]

There was a problem when soldering with TK83 because the maximum application temperature is 280 degrees Celsius I suspect that you overheated it and began to boil, after adding another portion of flux, it just cooled down and soldering went fantastic again. Because I am Polish and TK83 and LP-1 are Polish fluxes, I know a bit more about them, if I remember correctly, we used the AG-5 flux for soldering at higher temperatures (up to 400). We have used them for many years and in general AG TermoPasty products are very popular in our country (they are cheap but very good). By the way, the Polish word "Topnik" means Flux from the Polish word Topić - melt. I forgot to write, people start reading the manuals, there is all the information about the products you want to use. Thank you for this movie is very cool.

[@BahtiyarAliALHAS]

Hi; what do you know about rf800. I couldn't find the application temperature about it ?

[@tookitogo]

Ummm... the Weller flux says right on the tub that it contains zinc chloride, meaning it’s an acid based plumbing flux.

[@enteranon3342]

Yes it is IPA make this clumbi

[@artisrozentals5853]

Weller flux made me hardly detectable short-circuits, when applied to IC's. It wasn't detectable with multimeter, but only with infrared camera, when after a while, near VCC and GND heat started to abnormally build up. So be careful with it.

[@TonnyCassidy]

that weller flux reminds me of a blue tin solder grease made by stannol gmbh called lotfett, even comes with the same warning (contains zinc chloride) but the blue tin stuff have warning against using them for electronic or electrical soldering

[@RFC-3514]

I wonder if it's a Fluxite-type paste, with metal particles, meant to solder sheet metal and large power cables (not electronics components).

[@MikeyMack303]

In my experience, over many years, the amber flux paste is a great go to for best performance, no matter what label. Thank you for sharing that with us.

[@larsgregersen]

Thank you for this demonstration. Especially for showing the effect (or lack thereof) of not using flux at all!

[@sdgelectronics]

SOIC is about the limit for using no flux, but I have a video coming shortly for SMD IC soldering 👍

[@mietek7068]

Topnik is not a brand. It’s flux in Polish. But it’s nice to see them here. We have also quite good solder - the brand is Cynel (Yes, Cyna=Solder).

[@djalienprime]

Now perform the SIR test for all the fluxes from this video. I'm (almost) sure you'll be (unplesantly) surprised. The quality of solder joints is not the only important thing you should worry about: some fluxes remaining conductive or (even worse) creating a capacitance between the leads if not cleaned off. So you will have a bad time debugging your assembled device (especially on high-frequency parts: MCUs and quartz resonators).

[@onetech1627]

TRUE. I'm agreed with you.

[@user-zc8sd8jx8s]

yeah that's totally right. every flux comparison, unless you're using them to solder power wires or low-impedance low-frequency circuits, has to include a conductivity test.

[@ericeschborn1315]

thanks for sharing! As a hobbyist who only really has warmed my tip to soldering, it's refreshing to have such insightful videos

[@sahir3658]

Please Do a comparison on oxidized surfaces.

[@thepdails]

Updated link for the CIF? Are you still using it as your preferred option?

[@tonybell1597]

Excellent work, thanks, its always been the source of dilemma: "Which flux is best", heard across You Tube repair channels, so this is some really excellent advice, many thanks....

[@sdgelectronics]

My testing is probably in no way authoritative, but hopefully it gives some reference for anyone unsure. Thanks

[@johnyang799]

@@sdgelectronics Can we get a test of how fast does the flux get boiled off?

[@sdgelectronics]

@@johnyang799 yes, coming soon

[@jiribekr]

Many thanks for the extensive test! Bought 10pcs of fake Amtech NC-223-ASM based on Your test, and regret nothing. Much better than liquid fluxes and rosin I used before.

[@sdgelectronics]

Thanks! Glad it works for you

[@TheMechatronicEngineer]

One of the best flux comparison I've ever seen! What do you use to clean the flux residue?

[@sombatone]

Isopropyl alcohol

[@thesocker7920]

@@sombatone 99% ISP

[@cdyoutoob]

Would be good to see this done after 12-18 month with a broader range of fluxes. Perhaps ask viewers to submit flux suggestions. And also to have a review panels of other engineers / friends score the solutions. Could show off the corrosion of the test boards done from a year before so we can access long term viability of solder.

[@HunTomiBp]

I think this is the best I have ever met. ENGINEER ZC-70 Flux For Soldering 50ml - Japan

[@TheDefpom]

Can you do the same test with hot air please?

[@sdgelectronics]

Good idea, I'll give it a go.

[@user-vz4bo1en8x]

Mechanic is actually one of the best cheapo brands to work with, both solder wire, paste and flux works really nice.

[@MPETE1976]

Agree. I like that it is available in a wide variety of diameters and spool sizes for the wire. Paste in 6-7 or so tub sizes + syringes. Have yet to try the flux though.

[@OriginalMergatroid]

Excellent video. I have been using MG Chemicals flux pen that is a liquid flux. This is the stuff Nintendo recommended to us about two decades ago. I never did like it much and it was constantly bridging, especially on the last few pins. If course, those ships had over 100 pins so the gap between the pins was smaller. I just ordered some MG No Clean solder paste before coming across your video. I am happy it performed well in your tests. I would love to see some examples of how to resolder a BGA chip using this flux.

[@dimbulb330]

Very good presentation. Making the video two minutes longer you could have just mentioned the basic classification of r, rma, ra for each one as you went along, the same with the solder video. Again, well done.

[@sdgelectronics]

I have a couple of follow-up videos, so I'll be sure to include this info - thanks for the suggestion.

[@jamesdavies686]

Watching this again it's interesting how the solder climbs the component leg on some but not other fluxes, even if the flux did well with no bridges.

[@decem_unosquattro9538]

I started using Amtec - 559 -ASM - TF Expiry date June 8, 2023. I ordered it and it arrived 13 April 2023. I paid 79.91 AUD which to me was insane. Now its $198.12 which is really insane. 😂 I might get the CIF next. Thanks for the review.

[@Hackvlog]

I used to use some other liquid flux, but can't remember which brand it was. It had same properties as the ones you tested: More flux was needed for larger IC's. It either boiled away or spread so much, there wasn't enough flux around the last pins. Practice will make it better, but main cause is the properties of the flux. In my opinion liquid flux is very easy and quick to apply. I'll add TK83 to my shopping list, thanks to your video! Well done with the comparison!

[@sdgelectronics]

I think the liquid fluxes just aren't as suited to this particular style of soldering. It would be great for BGA style work as the liquid is drawn into gaps easily. It also cleaned off very easily. Thanks

[@johnnelson8714]

Something I learned from the school of hard knocks was to use the pitch from a pine, fur, etc. tree. It's also called resin. And it's free. Also to anyone using an acid resin on electronics DON'T! It'll eat the copper wire and the PCB board. (Friend did a repair on a board in his stereo wire acid core solder and it worked for awhile but eventually ate the board to the point he had to replace the board.)

[@ZoruaZorroark]

even though its been 26 years since my dad did soldering, i can still smell the flux

[@GeekDetour]

Excellent video! I am new to SMD soldering... so, I got a couple of soldering paste and flux - but they didn't perform as nicely as the best ones you've shown, BY FAR! I thought it was just my inexperience, my lack of technique, but your video showed quite some difference between them, I am purchasing the ones you recommended and then I can be sure what is my fault :) Thanks!

[@midrone4349]

Two things that are missing in this great test (unless I was sleeping). What is used to clean with after.. and what is the overall toxity. In eval, the residue and toxity should be counted. Its not optimal if the most toxic and polluting is ranged as best (Thats why lead is drawn from solder). Secondly, I would have liked to know about when to use paste or solder (i guess paste is for bare cobber).

[@RFC-3514]

How do you expect him to "count the toxicity", exactly?

[@javierpallalorden]

Thank you for the very comprehensive test, good to know that the fake Amtech is usable.

[@Boz1211111]

Though one of two or three worst fluxes here so no point in using imo. proskit and mechanic far better and still cheaper and are from china same as fake amtech

[@Blackwhite-oe7zg]

Relife 422 im halogen free is good flux. You know that?

[@habtamusium8646]

it was my gap to identify the flux and know how to apply them for my new business plan , now i begin my 1st step . many thanks ! lovely work .

[@hxhdfjifzirstc894]

I'm guessing people recommend Amtech flux because Louis uses it.

[@docferringer]

Yeah, though Louis says Amtech doesn't sell in on Amazon, so the stuff on eBay and Amazon is fake chinese stuff. YMMV

[@technicalgujarati8251]

He is God of macbook

[@jamesmurphy449]

@@docferringer Everything electronic on Amazon is fake.

[@Aethelbeorn]

@@jamesmurphy449 Just bought a Rigol 1257Z. It's real.

[@optimizelogicrepair2784]

@@Aethelbeorn same, I bought my Rigol DP832 from Amazon. Granted the seller was TEquipment, but I digress.

[@585585MC]

for me this is a wonderful channel. great tests, great video quality, great audio, great voice and speaking ability.

[@B24Fox]

I bought the BangGood tub of NT zs-18 flux, in both the white (as in the video), and amber colored paste. And I have to say that the white stuff is pretty horrendous! It spits everywhere the second you touch it with the iron. It almost instantly melts away from the joint leaving it exposed. And even if you use very much of it at once; it still doesn't help the solder flow too well. It's ONLY ok for basic soldering of wires and such... but TOTALLY not recommended for small microchip legs. The amber colored paste (although it comes in an IDENTICAL container color & sticker), is actually relatively decent. It's not too great with removing solder bridges for example... but if you use enough of it, it will eventually get you through (It does leave a pretty thick residue behind pretty quickly, so you always have to add more). It is good as a secondary paste, when you don't want to waste your more expensive good stuff (like from MG Chemicals for example). Also, they are both pretty thick at room temp. So If you're refilling another flux syringe with it; you're gonna have to really push to get it through the needle.

[@billybbob18]

I use Kester 63/37 with Kester flux. That combo works better for me overall than anything I've used. Almost everything I do is re-work. BGA joints NEED lead based solder IMO.

[@deadbluesky]

The Amtech NC-559 is sticky and hard to clean it work well but if you want a clean board after the job your not gonna like it, i use a lot of the Amtech RMA-223 one of my favorite also very affordable 50cc for $4, i also use jelly Yesa ET1030 for some work since it burn slower at high temp, i also like the Chipquik D291 or SMDLT when i use Chipquick for desoldering.... the ''Best'' compagnie is a copy of Amtech and Mechanic which i like soldering paste XG-Z40... But still prefer soldering paste ChipQuik SMD291AX... Best use the tools of Mechanics they just rebrand it and they also use the flux RMA-223 of Amtech. Nice video btw example is the best way to show what product peoples should use for their need.

[@CarlosMartinez-px9xo]

Hi, awesome video! I'm from Latin America and I've seen many weird fluxes. Some can ruin a board, like when liquid amber flux dripped on a hard drive and dissolved the copper. Sadly, I didn't see it for a month or two, so it was too late. I suggest trying a good board and switching pads between isolated and connected ones. This can act as a heatsink, change the performance, and show more differences between the fluxes.

[@robertcalkjr.8325]

Thanks Steve! Here lately I have been using Chip Quik SMD291 No Clean Tack Flux for SMD work. It seems to work great.

[@pa4tim]

I used that too, I loved it but Farnell took it out of their assortment. Now I use the Topnik TK83 (after trying several others). It is not as good as the Chip Quik but good enough. I liked the tacky stuff because it holds the component on its place (i use it professional for repair work)

[@sdgelectronics]

I used to use several different Chip Quik fluxes, but I noticed Farnell have dropped many of their lines, so it's not as easily available.

[@pa4tim]

@@sdgelectronics OK, you are right, it does not make sense to test it, if it is hard to get. I hated that I needed to find a replacement because the stuff is not cheap and I did not like the most I tested. The same goes for solder. Thanks, this was very interesting video.

[@robertcalkjr.8325]

pa4tim I am just a hobbyist but I am starting to get pretty good at microsoldering and using my rework station. I also try to always use my board preheater. The preheater makes rework easier for me.

[@robertcalkjr.8325]

SDG Electronics Hmm, sounds like Chip Quik needs to get on the ball! They are losing money!

[@thehitman5007]

I bought the Amtech knockoff version from china and im quite surprised on how good it is. So far so good, good flow. Just like the original.

[@imqqmi]

Same here, got chinese one from aliexpress and even after a few years the same flux works well.

[@martinwhite418]

@@imqqmi You guts should be Navy Seals, for you are quite brave.

[@frankpitochelli6786]

I often use a flux pen, it looks like a felt tip.... you push down on the tip and it soaks the tip....then it's applied to the joint to be soldered, however, for me it doesn't seem to work as well as the paste type fluxes, but it does the job....the syringe type fluxes can be tricky since they tend to glob it out per sae. But, IMO....most fluxes work just as well as the next, alot has to do with soldering techniques as well. Thank you for all the technical video's that you put together, they are alot of work for you tubers...but are very informative.!

[@wartlme]

Glad I found the video. This reminds me of "Project Farm" but for electronics. Just an honest review of products.

[@ameyjadiye]

Thanks for such a nice demo, it's quite useful even after two years to understand the in-out of the usability of flux. I have tried a few cheap fluxes with bad results. for me, the liquid one turned out to be the best one. thanks again for your guidance. I was also expecting this to be tried on raw copper endpoints to see the effectiveness.

[@rich1051414]

I use SRA Rosin Paste Flux #135. Kind of thick for SMD, but it's really tacky which I like.

[@sammccormick1]

I got some of the Chinese flux, which is very sticky and seems to be based on a type of paraffin wax. I mixed it with some (15% ish) mineral oil (corn oil in my case) and achieved a soft butter-like consistency that allows it to be loaded into a syringe, It performed the same as in the video however it was much easier to handle coming from a syringe. I used a 1mm metal tip on the syringe. Cost for 10 cc was approx $0.85 (115cc of flux cost $11 inc delivery). I am sure other types of mineral oil will produce similar results.

[@kuro68000]

"No clean" I've yet to find a flux that really is no clean on anything but the simplest boards.

[@rich1051414]

What that means is, 'no longer active when cool'. It will still look like snot crust :P It just won't hurt anything but your eyes.

[@pr0xZen]

While the point is that leaving the residues on there should cause no long term issues, two things to still consider is such: 1. If you _do_ want or need to clean it properly off, it usually will take more work and need solvents, ie not water soluable. 2. If there's a whole lot left on there, it could pose a nuisance or even challenge, for potential future troubleshooting, due to its material properties once all its solvent/suspension content has dissipated, and how it's _relatively_ significantly more work to remove (than water soluable flux). "Clear" ones shouldn't pose issues for visual inspection, but some leave a white residue that can obstruct visual indicators.

[@tookitogo]

​@@rich1051414 More specifically still, it means it's no longer active when cool AND after being fully heated to soldering temperatures once. Many no-clean fluxes are corrosive if they've been partly heated, as happens if you use it to tin stranded wire (where the flux melts and wicks under the insulation as the wire begins to heat, but long before it's reached soldering temperature). I'm running an experiment right now, where I took all the fluxes at work and from home and used them to tin some clear-insulated wire, as well as applying the same flux to another piece of the same wire, but not tinning or heating it all. Only one paste flux (a non-no-clean rosin flux gel) has caused corrosion on the unheated wire, but several no-clean pastes are causing corrosion under the insulation. (Same with some no-clean liquid fluxes.) In essence, most fluxes need to reach a temperature high enough to neutralize them. (The big exception is the water-soluble fluxes, which will remain corrosive no matter what, and thus must be flawlessly removed, making them unusable for things like stranded wire.)

[@zwerne42]

@@tookitogo Hey there. How are the experiments going?

[@japonicaren]

What type of solder did you use? Lead free? That's probably a good video topic of you haven't covered that yet. Temperatures and extra caution with lead free reflow timing etc.

[@unixoid33]

hi, my English is not very good, tell me which flux is better for soldering 21700 18650 batteries?

[@Shay_Nichol]

Since watching this video when it was released I've been using CIF at work and it's helped a lot! thank you!

[@pentachronic]

Very useful video. I've been using a liquid MG rosin flux for the last 5+ years and It's worked well but leaves a horrible residue which I have to laboriously clean with alcohol. Was looking for a newer style flux and your review has been very helpful. Just ordered through one of your links. Thanks.

[@allanknox8216]

CHANGE TO OA FLUX! You'll never look back.

[@nerijusk9598]

@@allanknox8216 what is OA flux?

[@allanknox8216]

@@nerijusk9598 OA flux stands for "Organic acid" it has stuff like citric and phosphoric acids - all water soluble. It's pretty aggressive and completely cleaned with warm water - no solvents. I only switched because every CM I worked with was already using it. Rosin flux has been out of favor for a long time. Chine uses no-clean to save money.

[@helenh9563]

Love this video, thanks so much! I do would like more emphasis on environmental impact of the different fluxes.

[@g4z-kb7ct]

I'm a bit surprised with the first flux result. I bought some years ago and I'm mostly doing re-work and repairs. This tub of 'stuff' is not flux. From what I've seen it has zero activate capabilities and really doesn't work at all. Certainly not on older parts. On a sop44 flash rom rework I put a blob of solder and added this flux and was not able to remove the blob of solder. Moving sideways just spread the blob to several pins that were all bridged together. I cleaned off the junk flux and put on some real smd gel flux (NC254, rather exensive but is very good) and touched the soldering iron and immediately the blob was removed. It's a shame as these tubs of flux are very good value if they worked lol. And yes, you can use an old shringe and scoop it up with a flat blade screwdriver and put into the shringe to make application less messy. The better way is to heat the flux gently until it is more liquidy (roughly 30C-35C) and just pour it into the shringe then you don't get air bubbles.

[@tonycstech]

If you solder with hot air, boiling temperatures and surface tension becomes a real issue especially with bga chips. For NC559 it's not a problem. Other flux brands may have low boiling point or evaporate too soon or have too much or too little surface tension be too thick or too thin causing all sorts of problems soldering small smd components. God forbid you use flux that requires cleaning on bga chip and don't do ultrasonic cleaning after. Pads will corrode causing unimaginable damage to your device.

[@fahedkhan3008]

You are a very good analyst. Very good video. Hats off.

[@markphilpot4981]

There are going to be those who disagree with me on this, but I am speaking from experience here and opinions vary. It’s better to use a flux which matches your solder’s flux core. This is enhanced by matching them both by brand. What you get is matching chemistries as they are made by the same manufacturer and therefore their chemistries are ideally identical. This yields consistent, reliable and repeatable results. It may not matter so much to some, but to those who’s lives are dependent on them, that’s a whole other conversation. If you can try that, you will see what I am saying is true especially when your methods are also consistent as that matters also. Stay safe mates!😊👍🏻😷

[@sdgelectronics]

Good point, at least using similar variants would improve things.

[@Voidsworn]

I ended up getting 5 tubs of the NT pretty cheap, like $12 and change. Still trying to figure out WHAT it is exactly. It just smells like some kind of wax/paraffin when heated and leaves a greasy residue that doesn't really clean off easily with IPA. I have a feeling it is less a flux and more just a heat transfer medium. I mean, it works for some SMT rework.

[@yrc4184]

Good to know that Polish "Topnik"(where do i live) flux is so good , no need to buy expensive one.

[@danfreeman8225]

Outstanding vid! Great layout, info and timing. Also excellent layout of links! I might suggest a couple things that might help. It could be handy to know the details of the solder you used and the temp (if you had a way to measure) and having video times next to the list in the description. Thanks so much, it really helped!

[@abeleski]

Thank you. Very interesting video. I would like you to expand your video to test a couple of other characteristics. Effectiveness on oxidised components and also even more important for me how fast the flux burns off. Especially important for hot air when a lot of times we have the heat on for a while. I believe the genuine amtech is what is supposed to set it apart from the others in this regard as it stays aroind for longer. Would be great to see some sort of a test for it. Thanks again.

[@sdgelectronics]

I'll work out a video with the same PCB, maybe removing and re-applying the IC with hot air. Thanks :)

[@abeleski]

@@sdgelectronics your current pcb is probably not a good example. You need those quad pack chips that have a big ground plane on bottom. Your current chip and pcb would be easy to remove with hot air. You need to simulate a large ground plane fighting off yoir heat gun if i am making sense

[@dankan4459]

@@sdgelectronics did you ever make the hot air station video? Great vids btw

[@XtremeKremaTor]

Myself I'm using topnik TK 83. You do need to apply a bit more of it using brush.

[@sdgelectronics]

It's also really good value and cleans off very well.

[@pibbles-a-plenty1105]

This method require a "spoon" soldering tip. An ordinary chisel tip won't to the job. Yes, go down the row of pins quickly. Don't apply so much flux, it takes a lot less to do the job properly (you need practice). Also, don't apply paste flux with a tooth pick. Trim the bristles on a small acid brush (or artist's brush with stiff bristles) and "paint" the flux on. With liquid flux use a slightly softer artist's brush. Clean your brushes with isopropyl alcohol (acetone works faster) and dry quickly with a cotton cloth or paper towel. You will waste a lot less flux and you won't run out of your party picks. 🙂

[@Foche_T._Schitt]

It would be interesting to know how they perform well past expiration.

[@KrotowX]

Now would like to see proper board cleaning from flux residue tutorial :) Although PRF 6-68 cleaner liquid with cotton swabs do the thing just fine, I'm curious about how to get flux residue out of bottom of ICs. What I noticed - JBC C245931 minispoon tip still do the job on QFP packages very good. BST-223 paste is not so good for small QFP ICs and USB sockets. Once fried few traces on board and one microUSB socket because used BST-223 and pins instantly got swamped under solder. Damaged bothsoccket and traces on PCB while struggled with excess solder cleanup.

[@VK6TT]

There is so much wrong with the drag solder technique you use. But I agree with your findings - no need to waste money on expensive flux.

[@TheAydinnet]

Did you use leaded solder for this test? It is really crazy how the solder just sticks to the pins :)

[@SidneyCritic]

Strange the cheap NT and fake Amtech worked so easy for you, because when I tested them the solder was hard to take and looked matt/frosty. I found some American Caig Brand locally down here that was night and day better, but it is like your Kester, ie: dark and hard to remove.

[@sdgelectronics]

I would hazard a guess that the cheap ones may be more inconsistent between batches, hence some variability.

[@SidneyCritic]

@@sdgelectronics You're probably right because my NT is yellowish where as yours is white.This was my result. kzbin.info/www/bejne/aZ_YgKBuea2Ed8k

[@deankay4434]

I am not a professional electronics builder or repair man. I have mostly tube plaster flux an use a simple tooth pick. I guess I don’t have many cocktail sticks laying around. As the cheap bastard I am, I use what I have an inherited a great deal of solder and flux. Liquid flux in bottle have the viscosity of water. They have readable factory labels but none say rosin or acid, only the rolls of solder show. I work with repairs on SMD’s, ribbon wire connections but all dirty & old. Cleaning to re-tin each is my hardest task. I have 3 types of heat soldering guns from low power stick types, to cheap gun shapes w/simple on - off switch. My last other than butane is a SnapOn 450 watt with three tips. Primary wire requires heat w/flux to clean. Already with shrink tubing, wires twisted laterally, I apply flux & heat. As the flux melts I apply solder immediately and works great. But tiny wires and tiny pads use on ribbon wire I find it hard to tin either. Controlling heat is important but the flux has to do its job. After applying a heavy body paste, I ready the solder and apply heat. I am trying to apply a ball to make the connection. Question; Does certain flux loose it’s cleaning ability with time? 1 year, 5 years or 20 years? I store it all in a cool dark location but still wonder. It only use enough heat to solder as overheating burns and creates a coating that’s hard to get thru. A common mistake used on copper water pipe by DIYers over & over again. I question rosin solder as it is formed with a line of resin inside as it is rolled into a stick and coiled on a roll. I bet it dries out with time. Even new stuff doesn’t work well without apply a paste first. Thoughts? Retired auto tech / fix it all. Thanks for the video and the work while the camera is off. Best of luck!

[@sdgelectronics]

The flux will degrade over time depending on what type is it. Rosin based flux has a significantly longer shelf life than any other.

[@Mr.Leeroy]

try martin bga gel flux. Personaly, I value more if flux produces as little smoke as possible, does not boil, spit or changes its viscosity under termerature too much. Secondly, how easy it is to clean, because this takes the most time and effort in the process of soldering. Then, how corrosive and conductive it is. And only then how shiny it makes solder joints, because margins are really negligable there.

[@Josh.Davidson]

Very good video. My (genuine) Amtech NC-559-V2-TF comes out a little more tacky then the one in the video though, which I found interesting.

[@BaronVonBeef]

Just ordered some of the banggood yellow flux paste because of this video

[@nigelman9506]

In one placed I worked at, I used a Flux pen with long bristles, it was like clear jelly and was fantastic on surface mount ic's with the solder pads underneath, did not evaporate and easy to clean, I don't remember the name of it

[@ocobotec]

Excellent video, I had been watching videos of solder paste all afternoon and this one is really worth watching.

[@hadiffnazhan862]

that cheap "NT" branded soldering paste was surprisingly good, around 2 dollars for 50g here in malaysia

[@kalle123]

You are soldering SMD with WELLER SOLDERING GREASE? Soldering grease for tin plating of copper, brass or steel sheet? DIN EN 29454-1: 3.1.1.C (Zinc chloride)

[@Omgbroccoli]

How about you test their corrosive action? This is very important for so-called "no-clean" fluxes, since a lot of people use them for cheapo bga rework and have terrible issues later.

[@jaro6985]

Thats my question as well. If they say "no clean" I would be willing to trust them. But some don't mention no clean at all, especially the Relife ones say "high activity" which is concerning, as it sounds like it could be RMA or RA type?

[@sdgelectronics]

Good points. I'll address this in the future when the test is complete.

[@Omgbroccoli]

@@jaro6985 unfortunately, most of no-clean fluxes from china are must-clean, especially fake amtech, mechanic and other rosin-glycerol based fluxes, since they contain a lot of fake corrosion inhibitors, that don't work as they should.

[@bobweiram6321]

The amber colored ChipQuik flux wets beautifully and performs even better than Amtech, but leaves a dark residue that's a little hard to clean.

[@fibranijevidra]

Nice comparison. It would be great if you could make v2 with other comparisons mentioned in the comments. You already have all those fluxes, so it would not take much effort.

[@subukai]

Thanks for the review. I ordered some of the Yellow Solder paste. It will probably take a couple weeks to get to me but the price was right.

[@jerm5772]

Is there a possibility that the each test was affected by the previous test from having remnants of flux on the soldering tip? You liked the results of the C.I.F. rosin test. So maybe the LP-1 rosin affected the C.I.F. test?

[@RFC-3514]

Flux generally evaporates well below the temperature of the iron. Even if he didn't clean the tip (which he probably did), he would have had to move immediately from one chip to the next to have any residue of the previous flux left on the tip. That's why flux core solder needs to be melted directly onto the item you're trying to solder (because if you apply it to the tip of the iron first, it boils / evaporates in seconds, before you can transfer it to the components).

[@els1f]

Man, your channel is incredible! So much great info 👍

[@imqqmi]

Agreed, it's a goldmine of info!