Flux Categories - Page 1
Forum section: electronics / beginners

author: 2X
author_rank: Frequent Contributor
timestamp: April 17, 2024, 09:21:02 pm
content: I am starting this thread especially for beginners in order to add informations about fluxes and misconceptions around the flux types and right uses. My favorite flux part numbers are the below.Every link, opinion are welcome.835-100MLVery good for soldering cables and SMD but not for hot air/reflow and not easy in cleanning (because is rosin based)https://mgchemicals.com/products/soldering-supplies/soldering-flux/rosin-flux/NC551-10CCVery good for soldering SMD and medium performance for hot air/reflow (because is rosin based)https://www.chipquik.com/datasheets/NC551-10CC.pdfSMD291Medium performance for soldering SMD, very good performance for hot air/reflow (because is resin based) and not easy in cleanning in respect with REAhttps://www.chipquik.com/datasheets/SMD291.pdfRMA7Very good performance for soldering SMD (because is Medium Activated), very good performance (higher viscosity in respect to others when it melts) for hot air/reflow and difficult in cleanning (because is rosin based)Can A Plumbing Solder Be Used For Electronics?https://blackdiamondtoday.com/blog/can-plumbing-solder-used-electronics/Choosing Soldering Fluxhttps://www.circuitspecialists.com/blog/choosing-soldering-flux/Flux Type Selectionhttps://evertiq.com/news/16783Choosing the Correct Flux – Types and Their Advantages/Disadvantages?https://www.pillarhouse.co.uk/technology/flux-choosing-the-correct-flux-type-technical-articleChoosing The Best Flux for High Quality Electronic Solderinghttps://www.chemtronics.com/essential-guide-to-flux-for-soldering-electronicsRosin Flux for Soldering – Flux Rosin Types and Classificationhttps://blog.gotopac.com/2020/03/24/rosin-flux-soldering-flux-rosin-types-classification/What They Don’t Teach You About Solder Fluxes on PCBshttps://resources.altium.com/p/what-they-dont-teach-you-about-fluxesWhat are halogens doing in a flux and what danger do they pose?https://smans.com/en/knowledgeportal/what-are-halogens-doing-in-a-flux-and-what-danger-do-they-pose/Electrochemical migration (ECM)https://www.google.com/search?q=electrochemical+migration&rlz=1C1KNTJ_elGR1079GR1079&sourceid=chrome&ie=UTF-8

author: tooki
author_rank: Super Contributor
timestamp: April 17, 2024, 10:28:29 pm
content: You say several times that particular fluxes are hard to clean “because rosin based”, but rosin fluxes are generally considered to beeasyto clean with solvents. It’s the modern no-clean fluxes that tend to be very hard to clean. So what is ityouconsider to be easy to clean??SMD291 is good. But I like SMD291NL even better — it handles higher temperatures for lead-free better without burning, and still works great for leaded solder, but its biggest advantage over the non-NL version is that the NL version is completely transparent amber, without any cloudiness. This makes it way easier to see what you’re doing.Also, you should link to the manufacturers’ pages, not distributors.The thread title is “flux categories” but you don’t actually explain the flux types at all! Never mind that there are numerous systems for categorization, and then orthogonal to that, the different forms in which each category of flux exists. That is, every type of flux (e.g. R/RMA/RA system, RO/RE/OR+L/M/H+0/1 system, or the F-SW system) exists as flux core wire, liquid, and paste/gel.

author: 2X
author_rank: Frequent Contributor
timestamp: April 17, 2024, 10:35:58 pm
content: I use Isopropyl Alcohol and cotton at the tip of tweezers for cleanning. Compare to these that I 've used I made a personal graduation about cleaning.

author: tooki
author_rank: Super Contributor
timestamp: April 17, 2024, 10:40:17 pm
content: Use proper flux cleaner. Modern fluxes are not fully soluble in IPA. (Traditional rosin flux is.)

author: tooki
author_rank: Super Contributor
timestamp: April 17, 2024, 10:41:02 pm
content: P.S. I updated my first reply after you responded, so you may want to reread it now.

author: 2X
author_rank: Frequent Contributor
timestamp: April 17, 2024, 11:06:37 pm
content: Quote from: tooki on April 17, 2024, 10:40:17 pmI had used the below flux cleaner but I didn't impressed with the results of the cleanning compared to IPA and also smells very bad. If you say that a flux cleaner cleans better than IPA then it will be like that. I will search to find and try another flux cleaner where at least his smell will be more "soft".Manufacturer Part Number: 84009-AA

author: tooki
author_rank: Super Contributor
timestamp: April 17, 2024, 11:17:37 pm
content: Quote from: 2X on April 17, 2024, 11:06:37 pmI’ve used Kontakt LR (aka Kontakt PCC) a lot, and it’s definitely better at cleaning than pure IPA, but the one I really like is Electrolube LFFR (lead-free flux remover). It cleans even better than Kontakt LR, and it smells a whole lot nicer (it uses orange terpenes as part of its solvent blend, which not only clean well but smell lovely).

author: 2X
author_rank: Frequent Contributor
timestamp: April 18, 2024, 08:58:13 pm
content: I found also the below cleaners and I wiil try one of them, but I am not sure for the results because on the datasheet shows that it needs 5 minutes in order to clean the PCB and also to put it on a secondary solvent in order to remove/rinsing residues/liquids from the clening step.I am going to try the below:COSOLV175-1.0https://www.chipquik.com/store/product_info.php?products_id=330062CHIPQUIK Flux Removershttps://www.chipquik.com/store/index.php?cPath=360

author: MathWizard
author_rank: Super Contributor
timestamp: April 19, 2024, 12:06:16 am
content: My current jar of cheap ebay stuff, it's like rosin mixed with wax. Trying to solder with it, well it's pretty weak stuff so it's lousy, but rarely have to worry about shorts with it. So anytime I have to work on SMD IC's, or something I can't easily clean, I use this.The other stuff I use, MG Chemicals 8342 RA rosin, it's great for eating corrosion and wetting, but it has to be well cleaned off afterwards. There's not much issue with large solder balls, but it can leave a conductive residue, and it spits and crackles everywhere. I've had it get under traces, and mess up a PCB I solder on too many times.On PCB's or protoboards, if I really want them clean, I use a toothbrush, ISP alcohol, and then soapy water. But yeah, I'm afraid too use that good stuff on chips and certain SMD stuff. I need to find something in between.

author: 2X
author_rank: Frequent Contributor
timestamp: June 26, 2024, 08:15:57 pm
content: I tried with hand cleaning the Flux Remover COSOLV175-1.0 but I am not impressed. I would say it dissolve flux residues 30% more easier than Isopropyl Alcohol and has smell were that is mildly affordable (with my nose at least). I use it only in special cases that I have plenty flux over hot air desoldering. I will continue to be fun of Isopropyl Alcohol.Also, I found that this make a very good cleaning with hands and with ultrasound cleaners (not only in flux residues buy and in corrosion – I haven’t tried yet).SWAS Safewash Superhttps://electrolube.com/product/swas-safewash-super/At 4:24 - SWAS Safewash Super

author: tooki
author_rank: Super Contributor
timestamp: June 27, 2024, 11:52:19 am
content: Quote from: 2X on June 26, 2024, 08:15:57 pmI’m not sure I’m understanding — if it cleans 30% better than IPA, why are you unsatisfied with it?Quote from: 2X on June 26, 2024, 08:15:57 pmI just got an ultrasonic cleaner at work, and I found SWAS to work very well. So did IPA (even on fluxes that resist IPA in hand cleaning). I also had great success with just water, when using ChipQuik’s water-washable no-clean flux (SMD4300 gel, and the equivalent solder wire). Of course, both for that and for SWAS, you need to have deionized water for a final rinse. (I’m lucky to have a DI water faucet at work.)

author: 2X
author_rank: Frequent Contributor
timestamp: June 27, 2024, 05:10:53 pm
content: Quote from: tooki on June 27, 2024, 11:52:19 amI don't like the smell of the COSOLV175-1.0 and also the IPA is more cheaper (at least here in my place). Maybe over the years I am totally addicted in IPA.

author: 2X
author_rank: Frequent Contributor
timestamp: June 27, 2024, 05:13:21 pm
content: "(SMD4300 gel, and the equivalent solder wire)"Do you have a part number of the solder wire?So did IPA (even on fluxes that resist IPA in hand cleaning)Yes I have seen it... the IPA with ultrasonic cleaner is far away more powerful at flux residues (I don't know if makes good job on PCB corrosion).Thanks for your reply.

author: tooki
author_rank: Super Contributor
timestamp: June 28, 2024, 02:40:38 pm
content: Quote from: 2X on June 27, 2024, 05:13:21 pmhttps://www.chipquik.com/store/index.php?cPath=600_610_611is the product category. I have the SMDSW.020 (I forget which size roll).

author: 2X
author_rank: Frequent Contributor
timestamp: June 28, 2024, 07:55:19 pm
content: Quote from: tooki on June 28, 2024, 02:40:38 pmI always be a bit of hesitate on solders and fluxes that cleaned with water but because everything you have said me is guarantee I will give a try. If you compared the Kester "24-6337-0010" with the chipquik water-washable no-clean how you will find the flow? The Kester for all the solders that I have used is on top of my list.P.S. Thanks for the link.

author: tooki
author_rank: Super Contributor
timestamp: June 29, 2024, 11:19:35 am
content: Quote from: 2X on June 28, 2024, 07:55:19 pmAs I told you via private message, even with the “water washable no-clean” (which expressly state the residues are safe to leave on), I didn’t feel comfortable trying them until I had access to an ultrasonic cleaner and unlimited deionized water. I certainly did not “guarantee” anything. Only a chemical analysis for ionic residues, and/or long-term aging results, would give us that.Quote from: 2X on June 28, 2024, 07:55:19 pmOn fresh components/boards with little to no oxidation, both work well.On more oxidized surfaces, the Kester 44 is decidedly better.

author: JJ_023
author_rank: Frequent Contributor
timestamp: June 29, 2024, 01:53:56 pm
content: I am no expert but this particular product I use for all of my needs. I know the datasheet is primarily for SMD and Wave but it works just fine for regular soldering.MG Chemicals - 8351-1L No Clean Fluxhttps://www.mgchemicals.com/downloads/tds/tds-8351.pdf