no clean corrosive flux vs non corrosive - Page 1
Forum section: electronics / beginners

author: TuxKey
author_rank: Regular Contributor
timestamp: April 17, 2018, 11:18:18 am
content: Hi guys,I just placed my first order of solder tin and everything i think i would need.With that order i chose an affordable liquid flux, because i saw how good of a job David did using flux i thought i might as well start with a small bottle to tryout.So i bought this "TE410/500"https://www.tme.eu/en/details/te410_500/fluxes/cynel/and this is the RF800/1 link:https://www.tme.eu/nl/details/rf800_1/vloeimiddelen/ag-termopasty/i was pretty sure it would be electronics save and it is no-clean..in my mail to tem.eu i asked if it was save for electronics and what the difference was with something like the more expensive RF800/1 but just got an answer days after my order of course..His answer was TE410/500 is save for electronics and is fairly similar to RF800/1 and that the difference in price is because the RF800/1 is non corrosive..i have mixed feelings about this answer.. As i don't fully understand what this means..so it's no clean meaning that it needs no cleaning and wont damage my board correct ?Still i plan on cleaning my work with an Isopropylalcohol mixture with acetone..as i found a diy flux remover on youtube.https://youtu.be/S99RjSC8VtYStill i thought the point of rosin was to be mildly corrosive and remove rust to let the solder flow easily to the joint ?am i worrying for nothing or will i damage my pcb's using this flux ?Or do i need to be extra careful and meticulous in cleaning my boardWill cleaning my work with a q-tips and my mixture be could enough..btw i thought that most if not all the rosin would evaporate while soldering ??Should i consider this flux a fail and try to get the RF800/1 instead ??Would appreciate any help guys..thanks again..btw don't know if that's important or not i'm mostly planning on soldering and desoldering mechanical keyboards at first and later on learn more an perhaps do more diy building..start of slow..

author: KL27x
author_rank: Super Contributor
timestamp: April 17, 2018, 08:24:07 pm
content: QuoteThe reason rosin is nature's flux is because these long rosin molecules are acidic when liquid. But you have to heat up the rosin to make it acidic. After the rosin cools down, it solidifies and becomes inert. It is also waterproof, so the metal salts that are left after the acid eats away the oxides are safely bound up in the rosin residue."Corrosive" doesn't necessarily equal acidic. An acid can't eat unoxidized metal. It selectively removes the metal oxide layer. So if the residue contains active acid and it also allows oxygen penetration to the metal, it is corrosive. If it contains halides (like chlorides/flourides), it is corrosive for an additional reason which is more specific to iron alloys. The halides penetrate and embed into the surface of iron and induces rusting on any exposure to oxygen and moisture. This provides oxidized metal for any active acid to eat away. And it also can cause connections to break, mechanically, because red iron oxide is bulky and spongiform and pushes itself apart.QuoteThe link says this is rosin based and halide free. And it can be cleaned with alcohol. It sounds perfectly fine to use on PCB's. I would imagine you can probably leave it on there with no ill effect in most applications. There's nothing there to suggest that this flux is (too) corrosive for electrical work. The datasheet and the "no clean" designation, and the placement of this product in this specific store ALL SUGGEST that this flux is designed and appropriate for what you're doing. If you don't trust that this is the case, then stick with rosin flux.QuoteIs that German?QuoteDon't put too much stock into this answer. People ask questions, and store owner must provide response. In another universe, you would get answers like "I don't know. These are just two different SKU's to me. We make a X percent margin on this one. We make Y percent on the other. People like variety and are pretty stupid. Some people like A because it's the first one they tried, and it worked fine and they will use it for 20 years until they die. Other people have tried B and they will swear by it until the day they die. We have to stock them all because having a variety of products is appealing to consumers. And there is a significant segment of the population which perceives higher cost as attractive. If you present them with 3 options, they automatically desire to have the most expensive one. Whereas if we only stocked that expensive one, it would be perceived as a ripoff."In short, there may be some important and significant differences between the two fluxes. The guy that answered your question might even know what they are. And he might have told you, correctly. But if he is talking out of his ass, he is always going to say something that justifies the cost of the more profitable (or at least more expensive) product. If not to sell you, at least to satisfy that you got a prompt response and weren't left hanging. But this guy probably spends at least 2 hours a day answering questions of customers buying thousands of different products which he has never even used.R, RMA, RA have a very specific definition. A manufacturer can make RMA flux and sell it as their own special "no clean." But unless it meets specs for RMA, they can't take any flux that works just like RMA and sell it as RMA, unless it is actually RMA. R, RA, RMA designators hold more "meaning" than "no clean," even if some no cleans are more or less the same as rosin fluxes. So if you are skeptical about what you have, you might want to buy a mil spec rosin flux for a baseline comparison.

author: TuxKey
author_rank: Regular Contributor
timestamp: April 18, 2018, 10:37:09 am
content: Quote from: KL27x on April 17, 2018, 08:24:07 pmi was under the assumption that this was rosin flux ??Quote from: KL27x on April 17, 2018, 08:24:07 pmhahah i understand the association no that's dutch i forgot all about the language settings i forgot to select eng before posting the link sorry about that..https://www.tme.eu/gb/details/rf800_1/fluxes/ag-termopasty/Quote from: KL27x on April 17, 2018, 08:24:07 pmi'm not one to judge a product by it's price guess i'm past that phase of life but not without ego as Leo from "actualized.org" would say..hahaha..Quote from: KL27x on April 17, 2018, 08:24:07 pmFor future reference and being able to recognize a flux that meets the specs you mention here.if i look at the product sheet of the "CYNEL TE410/500 " i bought and compare that with to other products on their site the first difference i noticed is the info line that says "Kind of flux" RMA for example this one.https://www.tme.eu/gb/details/10_1000/fluxes/kontakt-chemie/74527-002/or this one.https://www.tme.eu/gb/details/kalafonia-20/fluxes/ag-termopasty/The one i got doesn't say RMA just under the product name right at the top.. also no RMA in the Technical information i mentioned.if that's not what you mean here is the product link with all fluxes. (just as a refrence)https://www.tme.eu/en/katalog/#id_category=100484&cleanParameters=1&parameter_boxes=9&page=1&s_field=artykul&s_order=ASCthanks KL27x appreciate it. Your answer is both clear and insightful.Really happy to hear that i won't be messing my first build project. i'm going to keep your answer in my bookmarks as a reference..Thanks for taking the time and explaining it all to me / us noobs..Thanks for sharing the knowledge..

author: KL27x
author_rank: Super Contributor
timestamp: April 18, 2018, 11:45:55 pm
content: You're welcome. It sounds like have it figure out, now. But just in caseQuoteWithout delving deeper into the MSDS, the product info says that it is "rosin-based." Unless it is designated as "R/RMA/RA," it might not meet milspec for rosin flux... or it could be completely identical in ingredients to RMA but the manufacturer chooses to call it "no clean" for whatever reason they want. If it is sold as "no clean" you have to delve just a little deeper to see what kind of flux it is. In this case, it should likely be interchangeable and compatible with rosin fluxes. There is another "main" category of no cleans that are designed on the principle of barely having any active ingredients, and they are more specifically made for use in manufacturing, where the boards are pristinely clean to start with. They will have very little rosin (or synthetic resin) to encapsulate ionic residue/salt, so they will leave a very esthetically clean board. The industry lingo for this kind of flux is "low solids" flux.For the home gamer who uses lead solder, as long as you are avoiding no cleans that are low solids and/or incompatible with alcohol, you are probably fine with just about anything else labeled no clean. Or you could stick with RMA/RA and be good to go. But if you use lead-free solder or if you do BGA reflow, you may get better performance with some more specific fluxes.

author: helius
author_rank: Super Contributor
timestamp: April 19, 2018, 12:42:16 am
content: There is an even more specific standard than R/RMA/RA, called J-STD-004A from the IPC. It specifies 24 different flux types! The ones that are particularly suitable for hand-soldering of new electronic devices are ROL0.

author: wraper
author_rank: Unknown
timestamp: April 19, 2018, 01:44:08 am
content: Stay away from both of them. Although they both should be non corrosive, I'd care about their performance. Both are pretty low end brands and some products made by AG thermopasty are certainly crap IME. I'd suggest buying lower quantity (50-100 ml) of something better, you'll never spend 0.5+ l of flux before it gets bad.

author: TuxKey
author_rank: Regular Contributor
timestamp: April 20, 2018, 12:21:38 pm
content: i must admit that the two last comment left me a bit confused..@helius..At first i did not understand what you where saying but after 2e 3e reading i'm starting to understand you are basically saying there a litany of standards and in that list there are two of which one is suited for hand-soldering..could you point out one or two ? just so i know what to look for? Here is the EU store i can shop from.queued to the page with fluxes.https://www.tme.eu/en/katalog/#id_category=100484&cleanParameters=1&parameter_boxes=9&page=1&s_field=artykul&s_order=ASC@wraperi know they are low and , but i'm basically stuck with this one.https://www.tme.eu/en/details/te410_500/fluxes/cynel/unless i pay €7 to ship it back for a €5 product i can do two things use it with the knowledge that i will not damage anything.Or toss it knowing it can damage my pcb's and do more harm then good?KL27x already explained that it was save to use..Reading your comment makes me believe that i could have just wasted €4,40 on sum fancy alcohol with an acid.The Material Safety Data Sheet says this product has two ingredients1) isopropyl alcohol2) hexanedioic acidusing my own logic (as a noob in these matters) i would say the alcohol is just a way to carry contain the acid.Googling "hexanedioic acid" brought me to a paper of sum kind that talks about The Development of new Solderability of fluxes. Way, way above me...It does seem that hexanedioic acid is used in fluxes..but that's about it from what i can tell.And that the result was not disappointing. Still one paper doesn't mean anythinghttps://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=11&ved=0ahUKEwjyiKLg5cjaAhVBbFAKHRpWD5MQFgheMAo&url=http%3A%2F%2Fpublications.npl.co.uk%2Fnpl_web%2Fpdf%2Fmatc122.pdf&usg=AOvVaw3E0R1WI6OWPH_dhBljOG13One thing's for sure i need to re-read KL27x's answer and let it sink in..Also i plan on desoldering a few parts from a old router i have and soldering them back on using this leaded solder.https://www.tme.eu/en/details/s63hs10_0.7_0.5/solders-wires/stannol/543016/i will try and see if i can film the soldering part and how this flux reacts since i only have a phone camera (iphone6) i hope the quality is good enough for all of you to help me judge the quality..

author: helius
author_rank: Super Contributor
timestamp: April 20, 2018, 07:30:52 pm
content: I am not as familiar with European brands, but Amtech, Kester, Multicore, AIM, Indium, Alpha, MG Chemicals, are all quality brands. I can see that TME sells Amtech NC-559-TF, which is very good especially for surface-mount work.Quote from: TuxKey on April 20, 2018, 12:21:38 pmRosin flux may contain just pure rosin, but it commonly also contains activators. Common activators are adipic acid (hexanedioic acid), citric acid, and glutaric acid. These are all small molecules with multiple hydroxyl groups which helps them reduce oxides on metal surfaces. Your MSDS doesn't list rosin because in the form of flux, the rosin is not considered a hazardous chemical when it is spilled out of a truck on the highway. Don't over-rely on MSDS to tell you what's in things, it is only intended to inform those performing emergency cleanup.However, this particular flux is designed for wave-soldering machines, which means it is very thin. Flux for hand soldering shouldn't be as thin as this because it spreads out too much.

author: KL27x
author_rank: Super Contributor
timestamp: April 20, 2018, 10:04:30 pm
content: QuoteAccording to Wikipedia, hexanedioic acid has a melting point of 300F. So it's not just acid in alcohol. It's presumably an acid at soldering temps and a water insoluble solid below temps of most electronics. This is how rosin flux works. It might have some advantages or disadvantages over abeitic acid (rosin). Only one way to find out is to try it and see.Is it strong enough at removing copper and tin oxides, or is it just barely deoxidizing the surface of the solder to keep the solder flowey? Incidentally, almost any organic compound can be used to flux molten lead... wax, sawdust, oil, sugar... if it's made of C's, H's, and O's, it'll keep lead flowey. If it burns easily, it will work to take up oxygen. The question for electrical flux is at what temperature will it do this and what residue does it leave and can it dissolve copper and tin and iron oxides?Are the fumes objectionable?Is the residue harder/easier to clean than rosin?Is there some residual conductivity at temps up to, say 70C?Is it more or less tacky than rosin?Is the residue in fact significantly corrosive compared to other fluxes? (This is hard to tell without waiting a few years, lol; but it has an MSDS, and it's sold in a real store as "no clean," not alibaba/ebay-China. I wouldn't worry too much).

author: TuxKey
author_rank: Regular Contributor
timestamp: April 23, 2018, 03:21:42 pm
content: Good point @KL27x,i will answer all the questions as soon as i get my soldering iron.. TS100.Got the brand power supply tme.eu and all the other goodies..Just ordered my beginner multi-meter from lidl shop. added a helping hand sum fine needle noise pliers..pfff this hobby is getting expensive..well i suppose everyone has his midlife crises for me it's at 42 wanting to learn about electronics and solderingevery time i place an order it's like $50 then $100 and i'm starting cheap hahaha..ahh well guess that's normal when you realise your missing a lot of hardware..look forward to getting started.i'm also getting a few diy kits from banggood to practice soldering en using my multi meter.i'm very grateful for the knowledge your sharing. thanks again @KL27x