Solder - Page 1
Forum section: electronics / beginners

author: Kantilo
author_rank: Contributor
timestamp: April 20, 2021, 09:11:12 pm
content: Hello, I'm not sure which soldering tin to buy, I spotted the blue Kaina in China, and the multicore (I believe it's Loctite now), a link here:https://www.mouser.fr/ProductDetail/Loctite/395451/?qs=wnTfsH77Xs74F2EBk9Z91A%3D%3DThere are many different models for the same soldering tin, usually I take size 0.8, but there are 5C, 3C, 502, 511, I don't know what that representshttps://www.mouser.fr/Search/Refine?Keyword=loctite+0.8Thank you

author: mvs
author_rank: Frequent Contributor
timestamp: April 20, 2021, 09:50:42 pm
content: Quote from: Kantilo on April 20, 2021, 09:11:12 pm3C and 5C represent flux cores count.400, 502, 511 are flux types. 400 is halid free ROL0 flux. 502 and 511 are mild activated ROM1 fluxes.

author: Kantilo
author_rank: Contributor
timestamp: April 21, 2021, 12:39:08 am
content: Thank you for taking the time to answer me, for purely hobby use, what do you advise me between Kaina blue and Multicore? If the choice is Multicore I think I'll take the one I posted in the first link, maybe an alternative is better in the second link, about the flux

author: Shock
author_rank: Super Contributor
timestamp: April 21, 2021, 03:40:54 am
content: Stick with the Multicore as it's a well known brand and they provide safety data sheets for their products.

author: SilverSolder
author_rank: Super Contributor
timestamp: April 21, 2021, 03:45:20 am
content: This is a pretty good comparison, you can learn a lot from this guy:

author: Kantilo
author_rank: Contributor
timestamp: April 21, 2021, 10:07:41 am
content: Thanks for your reply, can I take 500G and cut it to wind it on a 50G spool roll for easier storage or does it damage the tin?Thank you

author: mariush
author_rank: Super Contributor
timestamp: April 21, 2021, 10:30:38 am
content: Yes, you can unspool and spool in smaller rolls, you won't damage the tin.The most harm you would do would be to have super low amounts of oxide forming on the wire as it's exposed to air while you unspool and spool... previously the wire was somewhat protected by the other layers of wire on top of them.But it's extremely small amount... AND it's super small time the wire would not be in a loop AND the flux inside the solder wire is there to attack much stronger oxidation than the amount that could possibly form on the surface of the solder wire in such a small amount of time. So I'd say it's fine.

author: wizard69
author_rank: Super Contributor
timestamp: April 22, 2021, 08:30:55 am
content: I've yet to find a decent flux cored solder from China. The MultiCore solder you have referenced should do fine for a variety of soldering chores. However that does not appear to be lead free solder if that is important to you.As for flux cored solder it is great stuff but it doesn't always replace the need for flux. So if you are going to order a roll of solder I'd also order some liquid flux. Depending upon what you are soldering a little liquid flux can do wonders even with flux cored solder. Also order some flux cleaner that is suitable for the fluxes you will be using.By the way there are other brands and alloys of solder that do work well. Kester is just one brand known to make high quality solders for electronics work.Quote from: Kantilo on April 20, 2021, 09:11:12 pm

author: SilverSolder
author_rank: Super Contributor
timestamp: April 22, 2021, 12:50:14 pm
content: In the video above, the reviewer showed the "Mechanic" brand of Chinese solder being surprisingly decent.I have a roll of it somewhere that someone gave me... haven't tried it yet.

author: Kantilo
author_rank: Contributor
timestamp: April 22, 2021, 03:18:32 pm
content: Quote from: wizard69 on April 22, 2021, 08:30:55 amThank you for your answer, to tell the truth I am thinking of using leaded tin, I have a lead-free coil and I'm not so happy with it, do you have some flux brands to advise me?Quote from: SilverSolder on April 22, 2021, 12:50:14 pmI came across this post, so I'm not sure, but I had three brands in mind:- Kaina (blue)- Mechanic- MuticoreQuote from: nanofrog on December 07, 2017, 02:48:57 am

author: SilverSolder
author_rank: Super Contributor
timestamp: April 22, 2021, 03:28:13 pm
content: If I can find my roll of "Mechanic", I'll let you know how I get on! I found it in the back of a drawer, and tried it on a couple of things (with flux added, like I would normally). I found it worked as well as any other 63/37 that I have - there is no obvious reason to avoid this brand, as far as I can tell from a quick experiment.Normally, I like to use solder with a small fraction of silver (e.g. 2%), it flows easier for me and looks much nicer when it sets (shiny surface), which I like for cosmetic reasons if nothing else.

author: mindcrime
author_rank: Unknown
timestamp: April 22, 2021, 06:06:48 pm
content: Quote from: SilverSolder on April 22, 2021, 03:28:13 pmHmm.. username checks out!

author: Shock
author_rank: Super Contributor
timestamp: April 22, 2021, 08:37:01 pm
content: Stick to the Multicore solder or Kester etc. Again avoid Chinese brands, the process of soldering producing fumes is bad enough without tempting fate.

author: Kantilo
author_rank: Contributor
timestamp: April 23, 2021, 12:13:50 am
content: Quote from: SilverSolder on April 22, 2021, 03:28:13 pmThank you for taking the time to answer me and for testing the tin to give me a feedbackI found Kester tin recommended by a lot of people, if I compare the prices, the Kester is 30 € for 500g, while the Mechanic is 20 € for 500g, maybe the Kester would be more interesting , on the other hand there are a lot of models, I found this onehttps://www.mouser.fr/ProductDetail/Kester/24-6337-0027?qs=1rIBfDHV7idbAy%2FP%252B2gNWg%3D%3D

author: mariush
author_rank: Super Contributor
timestamp: April 23, 2021, 10:01:11 am
content: That's nice. Maybe a bit too thick at around 0.8mm or whatever 0.031" ends up at.A possible alternative would be this one with 0.025" (~0.63mm diameter) and no clean flux:https://www.mouser.fr/ProductDetail/Kester/24-6337-8809?qs=m5JL4TdtMhzGbDU%2FtzkHHg%3D%3DIt would work better with smaller components, and if you need to solder big stuff you can always cut a piece of solder and bend it to have two parallel wires of solder.A small downside would be that it has only 1.1% flux core inside, which is fine if you're soldering new components but if you're dealing with a bit oxidized or crusty parts, extra liquid flux would help you.Flux is cheap if you buy it from the right places, I buy from tme.eu and i use the one in the first link below and works fine :3.2 euro 100ml TK83 :https://www.tme.eu/fr/details/flux-tk_100/flux/ag-termopasty/art-agt-045/3.7 euro 100ml LP1 :https://www.tme.eu/fr/details/flux-lp1_100/flux/ag-termopasty/art-agt-041/

author: JeanF
author_rank: Regular Contributor
timestamp: April 23, 2021, 12:04:35 pm
content: Quote from: Kantilo on April 23, 2021, 12:13:50 amHello, I've sent you a PM, I don't know if you have seen it. Nothing urgent, I'm just posting here in case you missed it !

author: Kantilo
author_rank: Contributor
timestamp: April 23, 2021, 03:03:44 pm
content: Quote from: mariush on April 23, 2021, 10:01:11 amThanks, I'm new to soldering, so no clean does that mean I need to buy some liquid to clean it? I see several times clean / no cleanQuote from: JeanF on April 23, 2021, 12:04:35 pmIndeed I did not see the message, I replied in MP, thank you for everything

author: mariush
author_rank: Super Contributor
timestamp: April 23, 2021, 05:26:30 pm
content: Quote from: Kantilo on April 23, 2021, 03:03:44 pmThere's all kinds of fluxes... a lot of them leave a bit of residue on the circuit board around the pad or lead or whatever you solder when you're done soldering .You need to think of fluxes as liquids that act like acids attacking the surfaces of the metals you want to solder when they get heated up by your soldering iron tip. They attack the surfaces removing oxides and crap making it possible for the solder to chemically react with the metals in the pads and leads of components.The solder has a core of solid flux in the middle of the wire which turns liquid or paste like at lower temperature than the actual solder around it ... as you bring the solder wire near the iron tip, the flux goes liquid and pours on the surfaces you want to solder and "attacks" them cleaning the oxides on the surfaces.The flux residue that remains around pads or leads, on the solder... very strong fluxes can continue to act like acids slowly eating into the pads and leads and over time you could end up with broken traces or other issues. Other flux residues can be a tiny bit conductive, so it could happen that the flux residue on a circuit board could behave like a very high value resistance between two pads on the circuit board, and therefore affecting the circuit.No-clean fluxes means the residue is not conductive and is not considered strong enough to continue attacking the surfaces once you're done. So, you don't have to clean the area once you solder. The same applies for most rosin based fluxes - you have basic Rosin flux, and there's Rosin Mildly Activated or RMA flux which is rosin plus some additives which make it a bit better, and you have Rosin Activated fluxes which is rosin with yet more additives and even stronger. Most of these 3 also don't need to be cleaned off the board, but always double check the datasheet.If you do want to clean the residue from the boards, it can be done with very easy to find isopropyl alcohol (probably anything above 97% purity would be fine, the 70% purity varieties are for hygiene, for killing bacteria off your hands, the lower concentration is better at killing stuff) or acetone (nail polish remover)... but keep in mind acetone can smudge paints, like printed text on plastic sleeves on components for exampleThere's some fluxes you should stay away from, like for example anything that says "Organic" or "water soluble". Organic fluxes are often much more powerful than needed and the fumes are much worse for your lungs and as for water soluble fluxes ... unlike no clean fluxes and rosin based fluxes, these must be removed from the boards and it's a complicated to clean them... the name is tricky, it doesn't mean you can just wash the board with regular water.Flux is very important in the process of soldering... it really helps. So a 3$ investment in a bottle you'll probably use for years is really worth it.Even with new components and new circuit boards, I like to apply a small drop of liquid flux on the pads of something I want to solder. Yes, the solder has some flux inside it, but more flux rarely hurts.It's also very useful at tinning wires for example... you can strip the insulation off a wire, put the wire inside liquid flux to get it wet with flux. Then, you can put some solder on your iron tip, basically make a big blob of solder ... by this time all the flux in the solder is burnt out, your iron tip has only solder... so the flux on the wire will do the work.... so now you can simply bring the blob of solder close to the wire and move it from side to side and solder will get onto the wire and tin it.See the videos below ...The first two explain really well how to solder... yeah, the videos SEEM outdated, but the techniques and explanations are still valid, so try to watch the two videos. First explains about solder and flux, the 2nd explains the technique of soldering... just don't stress too much about all that cleaning of pads and leads as it's not really that needed with modern stuffThe third video is about tinning wires ... the 4th shows a bit over the top tinning of a wire, but pay attention to the steps he makes and the techniquesolder and flux :technique :tinning wires and soldering to terminals (terminals are not used so much anymore these days)tinning wires paranoid level

author: wizard69
author_rank: Super Contributor
timestamp: April 24, 2021, 05:24:35 pm
content: On a hobby bench, maybe even a repair bench, a roll is likely to last you 20 years. That might mean 0.5 cents a day or half a penny. I just don't see it as worthwhile to shop for cheap in such a situation. It might be different in a production environment but then you would also have other specifications to meet.Your free to experiment with cheaper brands but what happens if you don't like them? You are out $20 and then need to buy another roll. Maybe I'm getting old, but there is something to be said for sticking with what you know works.Quote from: Kantilo on April 23, 2021, 12:13:50 am

author: Shock
author_rank: Super Contributor
timestamp: April 24, 2021, 05:33:34 pm
content: Quote from: camila on April 24, 2021, 05:08:56 pmI was going to mention Alpha Metals as well but they probably don't have it over there and I did a quick look on the web and couldn't find it easily. There is also AIM in the US which is made in Mexico and looks popular, not used it though. Stannol is however a popular brand in Europe and you can get Multicore and Kester from the large distributors.

author: DasDingleberg
author_rank: Newbie
timestamp: April 27, 2021, 12:54:49 pm
content: Piggybacking on OP, people here have an opinion on Kester 44? I figure more aggressive flux would be better for beginners.https://www.kester.com/products/product/44-flux-cored-wire

author: coppercone2
author_rank: Super Contributor
timestamp: April 27, 2021, 11:59:34 pm
content: I dipped non lead old solder in the ultrasonic to clean it up before, I don't think it hurts the flux so long you cut the end off, but with simple green it comes out more shiny and usable if you want to salvage it.I wonder if its not a bad idea to do it in general for critical applications before working so long you rinse it good with another ultrasonic water bath and DI rinse, there are probobly reasons not to do so.

author: tooki
author_rank: Super Contributor
timestamp: April 28, 2021, 01:28:18 am
content: Quote from: DasDingleberg on April 27, 2021, 12:54:49 pmKester 44 is great — it’s what I have at home right now. With that said, someone here on the forums recommended trying Kester 245, which is no-clean, but whose flux apparently significantly outperforms 44. I’m gonna try it when my roll of 44 runs out.

author: DasDingleberg
author_rank: Newbie
timestamp: April 28, 2021, 08:00:47 pm
content: Quote from: tooki on April 28, 2021, 01:28:18 am44 sounds pointless if true. Is mixing flux bad? Cos I already purchased RA flux with the same classification as 44.

author: Shock
author_rank: Super Contributor
timestamp: April 28, 2021, 09:29:08 pm
content: I wouldn't mix 44 and 245 on purpose but both are designed to be left on the board. 44 if left however shouldn't exceed 185C (probably will burn). Kester recommends cleaning both 44 and 245 with a saponifier (flux cleaner). You can get away with cleaning some rosin flux with IPA if you don't let it sit long, when it hardens it's more stubborn to remove. So individually mostly removal of those two flux is for cosmetic reasons.Note that you cant just magically add a solvent and expect flux residue to evaporate, it has to be scrubbed rinsed or wiped off and rinsed etc.Edit:Now that I have said this, I see plenty of people use a no clean flux pen with rosin core solder. Do they have problems, probably not. I tell people though to start at what flux you want to use then buy the wire that has the same flux if possible.It's best not to overthink unless you are willing to read up on all the different types of flux and applications, as the next person will say they use Kester 331 and your head will start hurting.

author: SilverSolder
author_rank: Super Contributor
timestamp: April 28, 2021, 11:06:55 pm
content: Sticking with the same type of solder for years "trains your brains" to know how it acts in a wide variety of situations - that saves a lot of time.So, to a beginner, I'd say - choose a good brand/type, and stick with it for a long time - your skills/learning will become cumulative that way.

author: tooki
author_rank: Super Contributor
timestamp: April 29, 2021, 05:26:43 am
content: Quote from: Shock on April 28, 2021, 09:29:08 pmDespite Kester’s instructions, Kester 44 does clean fully with just IPA. However, I’ve yet to find a flux that isn’t removed with less effort using proper flux remover.As far as being told to not mix fluxes: I think it’s more about process predictably than anything else. When looking at the ingredients of various fluxes, I noticed that there are plenty of fluxes on the market that contain the ingredients of both traditional rosin fluxes and modern rosin-free fluxes.

author: tooki
author_rank: Super Contributor
timestamp: April 29, 2021, 05:30:41 am
content: Quote from: DasDingleberg on April 28, 2021, 08:00:47 pm1. If an industrial or service process specifies a specific flux type, then that’s what will be used. I’m sure many, many processes still specify Kester 44.2. Traditional rosin fluxes like 44 are generally easier to remove than no-clean fluxes, whose residue tends to be much more stubborn. (In most situations, neither rosin nor no-clean residue needs to be removed, but when it does, no-clean is much harder to get off. They generally do not clean thoroughly with just IPA, demanding the use of a commercial flux remover. Though I recommend that anyway, see my previous reply above.)

author: Shock
author_rank: Super Contributor
timestamp: April 29, 2021, 07:45:16 am
content: Quote from: tooki on April 29, 2021, 05:26:43 amEasier to predict outcomes yes, it's why I suggest known branded rosin core lead or lead free with rosin flux, hard to go wrong from there. I would probably use Kester 44 myself but I have Multicore with Ersin 362 among others.

author: DasDingleberg
author_rank: Newbie
timestamp: May 03, 2021, 06:54:52 am
content: Do you recommend any particular flux remover?

author: tooki
author_rank: Super Contributor
timestamp: May 05, 2021, 11:49:58 pm
content: Quote from: DasDingleberg on May 03, 2021, 06:54:52 amEvery solvent-based flux remover I've used so far has worked well. Without comparing them side by side (since I haven't had them at the same time), I wouldn't say I've observed any huge differences between the ones I've used, but with the Electrolube product perhaps having a slight edge. (Or maybe I'm just imagining it, since I like its smell — it uses orange oils, and smells like it!)I've used Electrolube lead-free flux remover, Kontakt PCC (aka Kontakt LR), Techspray, and Distrelec's house brand, which is almost certainly made by Electrolube, since they were both made in England.All of them readily outperform simple IPA and/or ethanol, especially on no-clean flux, which leaves white residue when cleaned with just alcohol.In a nutshell, I'd check your favorite distributor and buy whatever their cheapest solvent flux remover is.I've also used Electrolube Safewash water-based (saponifying) flux remover. Worked great on rosin flux, but really struggled with no-clean. I think they make a newer formula that is more effective for that.