Why not lead-free - Page 1
Forum section: electronics / beginners

author: metebalci
author_rank: Frequent Contributor
timestamp: September 22, 2023, 06:27:37 am
content: I sometimes see here people saying they use or recommend 60/40 or 63/37. I am not soldering often and probably partly because of that I am not good at it but I did some reasonable SMD soldering for prototypes as well. Is there a reason why people still dont use lead-free solder ? I used SnPb solder many years ago and using lead-free for 5+ years and I dont see a too big difference at least not something affecting my hobby/prototype work. Am I missing something ? (I have a pretty good soldering station and using SAC305 type solder)

author: u666sa
author_rank: Frequent Contributor
timestamp: September 22, 2023, 07:32:29 am
content: 63/37 is a bit better than 60/40 when compared side by side.Lead free is brittle. So if you are replacing USB-C connector it makes absolutely no sense to stick it onto the same solder that made it fall off in the first place. Same with BGA when doing reball. Boards do get crooked and lead free does break connection. That said, there are some situations when lead free is used, almost always it is high temp scenarios. Power connectors on graphic cards. GPU's. CPU's.

author: ArdWar
author_rank: Frequent Contributor
timestamp: September 22, 2023, 08:11:34 am
content: Quote from: metebalci on September 22, 2023, 06:27:37 amI mean, it can work fine if you got the proper iron. At least until you try to drag solder a fine pitch TQFP or trying to manually solder a BGA without reballing.As for high temperature solder, I wish they're more widely used for board mounted modules. Nothing like reflowing your assembly and ends up discovering your module reflowed too...

author: wraper
author_rank: Unknown
timestamp: September 22, 2023, 08:19:37 am
content: Quote from: u666sa on September 22, 2023, 07:32:29 amLead free generally has higher tensile and shear strength but lower fatigue life. But there are different alloys with vastly different properties to begin with. Leaded solder is generally suggested for beginners because of lower melting temperature and because it flows better. Therefore it's easier to solder with and it's more forgiving to lack of a skill and good tools.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: September 22, 2023, 08:21:05 am
content: IME Leadfree flux fumes are nastier, though this probably varies by brand

author: wraper
author_rank: Unknown
timestamp: September 22, 2023, 08:24:24 am
content: Quote from: metebalci on September 22, 2023, 06:27:37 amTry soldering something with high thermal mass, like MOSFETs on a high end graphics card. Then the ease of work will become pretty obvious even for skilled person.Quote from: mikeselectricstuff on September 22, 2023, 08:21:05 amManufacturers produce solders with at least several different fluxes, so it's not just by brand but what type you buy.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: September 22, 2023, 08:26:04 am
content: Also, when I tried LF a few years ago, I found that tips didn't last very long, again YMMV depending on brand.

author: ArdWar
author_rank: Frequent Contributor
timestamp: September 22, 2023, 08:31:00 am
content: Nasty fumes and eating iron tips sounds like you got those aggressive activated organic/acid fluxes

author: wraper
author_rank: Unknown
timestamp: September 22, 2023, 08:32:20 am
content: Quote from: mikeselectricstuff on September 22, 2023, 08:26:04 amSome solders have nasty fluxes which when burning form particles that attach to the tip surface. Producing crust that is hard to clean, making the tip non wettable. I you have such problem, it's better to try different solder.

author: tszaboo
author_rank: Super Contributor
timestamp: September 22, 2023, 08:37:28 am
content: Leadfree melts at higher temperatures, has worse wetting, less reliable on the long term.When you want to replace a 2x1mm IC with 15 pins, for a one-off you really don't want to much about worrying abut your solder wire. So have a bit of 40/60 locked away where Mr Inspector cannot see it.

author: voltsandjolts
author_rank: Unknown
timestamp: September 22, 2023, 09:02:08 am
content: Quote from: tszaboo on September 22, 2023, 08:37:28 amHehe, glad to hear I'm not the only one!

author: tautech
author_rank: Super Contributor
timestamp: September 22, 2023, 03:12:32 pm
content: Quote from: metebalci on September 22, 2023, 06:27:37 amNever used it and have no place for it in my shack.My one and only reason is the additional heat required and the risk to the PCB traces from rework.Many modern designs are not laid out for simple rework when instead compactness is driving designs to reduce costs thereby helping to facilitate PCB swap repairs instead of board level repair for those few of us that can do it.Our throw away society is the principle driver of lead free muck and not product repairability.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: September 22, 2023, 03:27:04 pm
content: I tried to use lead-free solder a long time ago when it was first introduced. It was a top brand name spool but it was very difficult to solder with.Later someone gave me two spools of several kg each of leaded solder. It's more then I can use in my lifetime. But If I ever go reflow soldering, I will start with lead free solder paste and see how it goes.There is a catch you should now. A little bit of lead contamination in other wise lead-free solder does something strange with the alloy. I think the critical ratio is between 0.5% and a few percent of lead. In that range the (almost) lead-free solder becomes a mushy mess during soldering, and it also looses up to about 80% of it's strength.. You can get into this situation if you use the same iron for both leaded and non-leaded solder, and especially when you want to do repairs on a lead free PCB with leaded solder. If you notice this, then remove the mushy mess and apply fresh solder.

author: TimFox
author_rank: Super Contributor
timestamp: September 22, 2023, 04:04:21 pm
content: As an old man, I stick with SN62 (62 Sn, 2 Ag, 36 Pb) rosin-core solder, since I know how to use it.For anyone starting their career now, who intend to do a lot of soldering, I recommend learning how to use Pb-free solder, since the regulations will require it in commerce.I remember when this first started, an early exemption was granted to cardiac pacemakers (despite inserting toxic lead into the body) due to concerns with joint reliability.Is this exemption still true?[edit: corrected solder formula typo]

author: radiolistener
author_rank: Super Contributor
timestamp: September 22, 2023, 04:14:43 pm
content: Quote from: metebalci on September 22, 2023, 06:27:37 amNot all peoples believe in these conspiracy theories that using solder lead is extremely highly dangerous due to lead is absorbed by the body, increases greenhouse gas emissions, glaciers melting and after all will destroy our planet...Quote from: TimFox on September 22, 2023, 04:04:21 pmAs I know, military, space and avionics equipment also allows using it. It will be too hard to repair some electronic module on a deep space satellite when it fails due to bad reliability of soldering...For consumer electronics broken soldering after several months of usage is not an issue, but required feature. And this is where lead-free solder is the best.Each technology has it's own pros and cons

author: AndyBeez
author_rank: Frequent Contributor
timestamp: September 22, 2023, 04:34:48 pm
content: I once had a small reel of SN99C solder wire which, thanks to the added trace ofgeraniumgermanium, made it very workable on the bench - wettable to work and solidified shiny. Lead free soldering was a positive experience. I have not found any in recent years (outside of Japan or China). Available formulations of 'hobbyist' LF seem to eat solder tips at 330C.Given how RoHS is for mass market electronics, which in Europe is covered by the WEEE protocol, home electronic building and repairing with 60/40 is not ever going to harm the world's ocean life.Anyway, I would argue that in the lab, the phenols in the flux smoke are 1000 times more hazardous than the lead in the solder. And soldering LF is hotter, which makes more smoke.Lead free? Only if needed.

author: Bud
author_rank: Super Contributor
timestamp: September 22, 2023, 05:09:20 pm
content: I'd like to turn the question around and ask why to use led free. Beside regulatory compliance i see no reason. If you are a factory then yes by all means. Other than that everything is worse, high temperature, reduced tip life, increased risk of component damage, risk of board warping, nasty fumes, shitty appearance, tin wiskers growing over time, higher power consumption by soldering equipment. Sorry if I forget anything.

author: TimFox
author_rank: Super Contributor
timestamp: September 22, 2023, 05:29:43 pm
content: Quote from: radiolistener on September 22, 2023, 04:14:43 pmThe bad effects of lead on children are clearly proven: lead paint eaten, lead leaching into water supplies, lead tetraethyl (leaded gasoline) in the atmosphere, etc.How much lead leaches out of solder in cell phones into humans is not clear.https://www.cdc.gov/nceh/lead/prevention/health-effects.htmhttps://www.pnas.org/doi/10.1073/pnas.2020104118https://www.dshs.texas.gov/blood-lead-surveillance-group/general-lead-exposure-information/effects-lead

author: radiolistener
author_rank: Super Contributor
timestamp: September 22, 2023, 05:56:42 pm
content: Quote from: TimFox on September 22, 2023, 05:29:43 pmBefore 1970, the same guys claimed that leaded gasoline (with tetraethyl lead) is proven as completely safe and there is no evidence of harm for people... And it leads to extremely high contamination of Earth environment with lead, even on Greenland and the North Pole detected exterme high rise of lead concentration due to that leaded gasoline... And now the same guys talking about harm from leaded solder...I think this is just unfair business, such restrictions allows to have monopoly and get money from that. But it definitely doesn't depends on harm, just because much more harmful things are "proven as completely safe" and much more safe things are "proven as completely and very harmful"...

author: coppice
author_rank: Super Contributor
timestamp: September 22, 2023, 06:05:07 pm
content: I don't know of a currently available non-lead solder that is suitable for high reliability applications. There are exemptions in the lead free rules specifically for things like medical products. However, the "lead is OK" market has become sufficiently niche that all new components I know of are now pretty much lead free, unless lead is an active part of their function (e.g. lead shielding to contain x-rays). It took a long time for the lead to be eliminated from many of them. When you see the list of metallic elements going into things like IC lead frames, it can be quite long.

author: metebalci
author_rank: Frequent Contributor
timestamp: September 22, 2023, 06:13:09 pm
content: Quote from: Bud on September 22, 2023, 05:09:20 pmVery hard to make this question work for everyone, as everyone's conditions or requirements are different, and maybe mine is very specific. For me the health effects are the most important one. It is not a factory (I dont sell them) and not even a small repair lab (I dont fix old things), I do tiny amount of soldering only when I have to, so I dont care about reduced tip life, energy consumption etc. I guess I damaged a component or PCB a few times which I can live with, never experienced board warping (I did not need to solder large areas yet if it is related), and it is for prototypes so I dont care about the appearance or even medium-long term reliability (yes I sometimes make something I plan to use long term, but nothing had a soldering issue yet after a year or two). So I think for me it comes to the point, is it better to handle lead or better to have probably more fumes (due to heat?) from flux ? I use no-clean L0 so it is the minimal amount of rosin core flux (I dont know or used if anything with no rosin works well), and I also order PCBs as lead free and I rarely need to modify something on new development boards which are also lead free.edit: I also do not solder large ICs, usually 8-16, rarely 20-24 pins, most of the time smds. I havent tried a tqfp 32 yet.

author: IanB
author_rank: Super Contributor
timestamp: September 22, 2023, 06:30:55 pm
content: Quote from: TimFox on September 22, 2023, 04:04:21 pmYes, I think that exemptions for mission critical applications like aerospace and medical are still in place. I think this is largely because the reliability of leaded solder processes has been proven over decades, and the reliability of lead-free is unproven. You cannot use unproven processes where quality assurance is required. (This is much the same reason that nuclear power plants still maintain and use control systems that are 40 or 50 years old.)My personal impression is that boards made with lead-free solder will tend to fail after only a few years due to joint failure. I suspect that manufacturers secretly like this as it forces customers to discard failed products and replace them with new ones. Products made with leaded solder would tend to last forever and only fail eventually due to component failure (e.g. electrolytic capacitors or switches).

author: radiolistener
author_rank: Super Contributor
timestamp: September 22, 2023, 06:34:28 pm
content: Quote from: metebalci on September 22, 2023, 06:13:09 pmI'm sure that you never have thoughts and even don't know about effects from leaded gasoline on your environment and your health, but this effect is million of times higher than effect from leaded solder. For some reason, you're scary and thinking about effect from leaded solder, but not about effect from leaded gasoline...There is another example, of "proven safety":Japan to release Fukushima water into ocean from Aug. 24. But people don’t notice this, they are concerned about all sorts of things like the harm from lead solder or the harm from cows’ digestive gases for the Earth’s atmosphere...It's fun to see how people worry about trifles, point blank not noticing the really serious dangers

author: IanB
author_rank: Super Contributor
timestamp: September 22, 2023, 06:46:54 pm
content: Quote from: TimFox on September 22, 2023, 04:04:21 pmQuote from: metebalci on September 22, 2023, 06:13:09 pmIt's worth remembering that metallic lead is very inert and hard to be absorbed into the body. Water pipes were made from lead or lined with lead for centuries. Lead has also been the preferred material to contain corrosive acids in industrial plants because of its resistance to chemical attack. Honestly, you could swallow a lump of lead and it would pass straight through your body untouched.It is lead compounds that are dangerous, not the lead itself. This means that lead in gasoline was bad, and lead in paints likewise. But for the lead in solder, the main concern seems to have been about lead getting into landfills when products are discarded. That has to be compared with lead free processes needing more environmentally harmful fluxes and solvents, and the greater amount of e-waste generated from more frequent product failure.

author: coppice
author_rank: Super Contributor
timestamp: September 22, 2023, 06:56:11 pm
content: Quote from: IanB on September 22, 2023, 06:46:54 pmThe biggest lead hit most people get these days is their first cup of tea or coffee in the morning, made with water that stood for quite a while over night in lead pipes. Pure lead housing pure water has a very low rate of solution, but most drinking water has enough dissolved material to keep a modest level of reaction going.

author: TimFox
author_rank: Super Contributor
timestamp: September 22, 2023, 07:07:34 pm
content: Quote from: radiolistener on September 22, 2023, 05:56:42 pmThe conspiracy statement is NOT a quotation from me.Which "same guys" said tetraethyl lead is completely safe?Where they employed by petroleum companies?

author: metebalci
author_rank: Frequent Contributor
timestamp: September 22, 2023, 08:10:05 pm
content: Quote from: radiolistener on September 22, 2023, 06:34:28 pmI have a specific question about solder. Not a risk analysis of things to my health.

author: metebalci
author_rank: Frequent Contributor
timestamp: September 22, 2023, 08:13:39 pm
content: Quote from: coppice on September 22, 2023, 06:56:11 pmLead water pipes ? To my knowledge, banned in early 1900s.

author: metebalci
author_rank: Frequent Contributor
timestamp: September 22, 2023, 08:25:33 pm
content: Quote from: IanB on September 22, 2023, 06:46:54 pmIt seems the main route is not through skin absorption but ingestion through surface contamination.The paper below also mentions rosin core flux in lead-free solder due to high heat, so that point seems to be very valid. Not sure yet the difference between L0 and others but definitely logical to look for rosin-free fluxes.https://www.ehs.harvard.edu/sites/default/files/soldering_safety_guidelines.pdf

author: coppice
author_rank: Super Contributor
timestamp: September 22, 2023, 08:35:41 pm
content: Quote from: metebalci on September 22, 2023, 08:13:39 pmLead water pipes? To my knowledge still massively deployed across a number of countries.They may have health issues, but they are so damned good at carrying water they just don't motivate people to spend large amounts replacing them. They were still the standard form of water pipe for new housing estates in 1930s in the UK. I'm not clear when new installations ceased.

author: TimFox
author_rank: Super Contributor
timestamp: September 22, 2023, 08:37:24 pm
content: Quote from: metebalci on September 22, 2023, 08:13:39 pmLead water pipes, specifically the "service line" pipes from the water main (typically under a street) to an individual house, are still a problem in the US.They were actually mandated in Chicago up until 1986.https://sli.chicagowaterquality.org/At present, the civic authorities have started an effort to replace about 400,000 such lines, but meanwhile the water department adjusts the water chemistry to minimize leaching.

author: coppice
author_rank: Super Contributor
timestamp: September 22, 2023, 08:49:15 pm
content: Quote from: TimFox on September 22, 2023, 08:37:24 pmThe 80s was the key time for killing off lead in lots of applications, like gasoline and paint. Is it true they still produce lead paint for some applications in the US?Lead pipes just works so very well. They are fairly soft and pliable. The same reason lead works so well for solder. A little ground shifting doesn't fracture them, but they are stiff enough that they rarely crush and cut off the flow. Much of the lead pipe network in the UK was installed under our old queen - not Lizzy, Vickie. Stop cocks may have been serviced and replaced since then, but the pipes themselves go on.That chemistry issue was what the Flint water debacle was all about. The lead pipes were not a big issue until penny pinchers changed things, and the impurities in the water started strongly leaching the lead. Probably much of the world's lead pipe is quite benign, because the water it carries doesn't allow it to leach.

author: metebalci
author_rank: Frequent Contributor
timestamp: September 22, 2023, 08:50:43 pm
content: Quote from: coppice on September 22, 2023, 08:35:41 pmI dont know other countries but from the Swiss national broadcaster website: "The Swiss first responded to the danger of water contamination in 1914 by banning the use of lead pipes in water piping." I guess it might have taken some decades to disappear but I dont think there is lead water pipe now, particularly not in buildings from last 50 years or so. I read in other pages it is similar in France but there might be lead pipes in old buildings in Italy and Germany. So yes I think you have right, it depends a lot on the country, also probably city and the building.

author: coppice
author_rank: Super Contributor
timestamp: September 22, 2023, 08:57:57 pm
content: Quote from: metebalci on September 22, 2023, 08:50:43 pmIt would be interesting to see how much lead pipe remains in those places. Like I said, lead pipe just goes on and on working well, not needing replacement. Its hard to get people to pay to rip out and replace working infrastructure. Its the old last mile/kilometre problem.

author: metebalci
author_rank: Frequent Contributor
timestamp: September 22, 2023, 09:14:42 pm
content: Quote from: coppice on September 22, 2023, 08:57:57 pmFor Switzerland, it seems to me like there is none (for clean water). I read the alloys might contain residual lead so in 2007 they also further restricted it. I think maybe the bigger problem here is the lead paint in old buildings if not renovated for a long time.I saw an EU paper from 2010, it was saying 25% of homes in Europe might have such pipes and 2/3 of them might be problematic.

author: TimFox
author_rank: Super Contributor
timestamp: September 22, 2023, 09:18:52 pm
content: Before ROHS attacked lead-bearing solder in electronic applications, it was banned in the US by Federal legislation in 1986 for potable water plumbing.https://www.epa.gov/sdwa/use-lead-free-pipes-fittings-fixtures-solder-and-flux-drinking-water

author: IanB
author_rank: Super Contributor
timestamp: September 22, 2023, 09:22:28 pm
content: Quote from: metebalci on September 22, 2023, 08:50:43 pmBear in mind the lead pipes are not necessarily in buildings, but rather buried underground, beneath the streets, in the municipal supply lines. For sure, many streets have been dug up over the years and the pipes replaced with polyethylene, but if you want to find lead pipes that is where they will be, hidden out of sight beneath the surface.

author: Wolfgang
author_rank: Super Contributor
timestamp: September 23, 2023, 10:14:13 am
content: IMHO, 60/40 is easier to solder manually, has better mechanical strength and less reliability problems. Aerospace and MIL still use it today for hi-rel missions. As long you use it on a small scale for hobby use I think the environmental drawbacks can be tolerated.

author: tooki
author_rank: Super Contributor
timestamp: September 23, 2023, 11:20:18 am
content: Quote from: Wolfgang on September 23, 2023, 10:14:13 amWhat surprises me is the people who swear by 60/40 leaded instead of 63/37 eutectic, which is less susceptible to disturbed joints (faulty joints caused by movement during solidification). I find 63/37 much nicer to work with. In the past, 63/37 was a bit more expensive than 60/40, so the latter was widespread. But nowadays, since lead-free is mainstream and leaded is a comparatively niche product, 63/37 and 60/40 cost the same, and sometimes 60/40 actually costs more.Quote from: Wolfgang on September 23, 2023, 10:14:13 amLead-free is actuallystronger. But it’s less ductile (=more brittle). Leaded solder is more flexible, which makes joints less likely to fracture, but possibly more susceptible to other types of damage (like stress from thermal cycling).Quote from: Wolfgang on September 23, 2023, 10:14:13 amNow that the electronics industry is accustomed to working with lead-free and has optimized the designs and processes, I don’t think there’s any truth to the claim that it’s less reliable. (And while there’s lots of conjecture about it being less reliable, there’s little hard data to support this.)Military and aerospace are staying with leaded not because there’s true evidence that lead-free is inferior, but rather because it is not thoroughly tested the way leaded is. The effort and cost to recertify everything on lead-free would be enormous, with no obvious advantage.*The only real reliability issue is metal whiskers, which affect pure tin plating (and other pure platings like zinc, IIRC). Thorough tinning with leaded solder is one way to eliminate pure tin plating, but it’s not the only way. Tin whiskers have affected aerospace equipment assembled with leaded solder, since the problem isn’t the solder, but the component plating.*The lack of obvious advantage is my feeling about the switch to lead-free in general, but that decision was made by posturing politicians, not scientists and engineers… Sorta. When RoHS was conceived, electronics contained tons of lead — but nearly all of it was in the lead glass of CRTs, which used kilos of lead in a typical tube. RoHS didn’t predict the demise of the CRT. The lead in solder was trivial, but ended up being the main source of headache in RoHS compliance. If it were up to me, we wouldn’t have banned lead solder, but that ship sailed long ago, and modern lead-free solders and fluxes work great! (Don’t base your impression on early lead-free solders, which had inferior fluxes and alloys.) I think the quality of the flux is often underappreciated. Most fluxes that were adequate for leaded solder aren’t good enough for the inherently inferior properties of lead-free solder, and don’t hold up under the higher temperatures. The best modern fluxes overcome all of those limitations very well. But if you get lead-free solder with inferior flux, you’ll be disappointed. For example, Stannol solder is widespread in the German speaking world, but IMHO their solder wires suck. None of their fluxes perform as well as I like, and they spit a lot. (I don’t even like their leaded solders.) In contrast, Felder (another German manufacturer) makes lead-free solder that is a joy to work with, and costs less to boot…

author: coppice
author_rank: Super Contributor
timestamp: September 23, 2023, 11:24:51 am
content: Quote from: IanB on September 22, 2023, 09:22:28 pmAt some point people will be demanding those plastic pipes are dug up and replaced, because of leaching of nasty materials they contain. Its an endless cycle.

author: metebalci
author_rank: Frequent Contributor
timestamp: September 23, 2023, 01:25:26 pm
content: Quote from: tooki on September 23, 2023, 11:20:18 amJust to add to this, I saw papers both from NASA and ESA already testing lead-free. Very recently during the development of ESA Euclid mission, they have tested relevant things and I saw there is at least a high-level roadmap to switch to lead-free in 10 years.

author: Monkeh
author_rank: Super Contributor
timestamp: September 23, 2023, 01:40:07 pm
content: Quote from: tooki on September 23, 2023, 11:20:18 amIn my experience, the difference between 63/37 and 60/40 is pointlessly negligable (hence 60/40 existing, as it's easier to just not bother being precise enough for a clean eutectic alloy), and I've never seen 63/37 available at an equal price point. I suspect that reversal is only occuring in certain markets due to the general death of leaded solder except among die-hards unable to fairly judge other materials (no, I'm not directing that at you.. although I disagree that 63/37 is meaningfully better).Regardless, due to working with RoHS I've had no choice but to just use lead-free, and quality alloys and fluxes make the only observable difference a slightly longer dwell time. Well, that and the price being three times what I last paid for a roll of 60/40. All I want for xmas is a reasonably priced roll of SN100C..Quote from: tooki on September 23, 2023, 11:20:18 amZinc certainly does it - lift up a hot-dipped steel floor tile some time and you'll find a furry surprise, and it's not the spider.Goddamn googly-eyed archno-terrorists in my trousers...

author: Wolfgang
author_rank: Super Contributor
timestamp: September 23, 2023, 02:06:30 pm
content: Quote from: tooki on September 23, 2023, 11:20:18 amWG: Whats your favorite lead free and leaded solder brand ? Maybe I give it a try.

author: coppice
author_rank: Super Contributor
timestamp: September 23, 2023, 02:36:03 pm
content: Quote from: tooki on September 23, 2023, 11:20:18 amThat's not the only reliability issue. The lead free solders seem more susceptible to cracking. Rather like leaded solder when you are sloppy about getting gold pollution in it.The whisker problem doesn't only affect pure tin. I've seen thick lumps of leaded solder form a huge tangled mass of whiskery fibres when left undisturbed for decades. It was really quite a surreal sight. Just what provokes these materials to form whiskers, when most samples of an affected product stay completely free of whiskers for decades seems poorly understood. The thing with unleaded solder is the whisker problem changes from a rare event in leaded solder to a relatively common event.

author: Wolfgang
author_rank: Super Contributor
timestamp: September 23, 2023, 04:30:19 pm
content: Never seen whiskers with 60/40 solder. Maybe the parts soldered were tinned ?

author: radiolistener
author_rank: Super Contributor
timestamp: September 23, 2023, 04:52:22 pm
content: Quote from: metebalci on September 23, 2023, 01:25:26 pmI have no doubt that NASA or ESA can spend trillions of dollars to use modern nano and pico-technology just to develop some very expensive lead-free metamaterial which can give you the same or even better properties as lead solder. But unfortunately such approach doesn't works for a usual electronics amateurs who don't have trillions of dollars from tax payers to spend it on something very expensive just for fun experiment...And after all, NASA/ESA still using lead solder, despite the fact that there are a lot of wonderful lead-free solder on the market. Have you ever wondered why?Each technology has it's own pros and cons. And since consumer electronics needs very short lifetime, lead-free solder is the best here. Other industry has different requirements and it appears that lead solder or something other more expenisve is better for that. There is no ideal solution which is the best for any requirements.

author: metebalci
author_rank: Frequent Contributor
timestamp: September 23, 2023, 05:14:28 pm
content: Quote from: radiolistener on September 23, 2023, 04:52:22 pmI said this because of comments about the use of lead free in space tech. Do you expect them to switch to lead free in a day ? Naturally it requires millions and years, as it is spent before for anything to be used in space.

author: tooki
author_rank: Super Contributor
timestamp: September 23, 2023, 05:52:23 pm
content: Quote from: radiolistener on September 23, 2023, 04:52:22 pmBecausecertifyingits reliability is time-consuming and expensive. For those applications, one needs near-absolute certainty. There can be ample evidence that it’s good, but they want proof.The fact that something hasn’t been certified yet doesn’t mean it’s not good enough.

author: tooki
author_rank: Super Contributor
timestamp: September 23, 2023, 05:54:35 pm
content: Quote from: Wolfgang on September 23, 2023, 04:30:19 pmIt has happened on equipment long before lead solder was used.https://nepp.nasa.gov/whisker/failures/index.htmAll of that is with lead solder.

author: tooki
author_rank: Super Contributor
timestamp: September 23, 2023, 05:59:23 pm
content: Quote from: coppice on September 23, 2023, 02:36:03 pmYep. I know. Literally the next thing I wrote in that post was:Quote from: tooki on September 23, 2023, 11:20:18 amQuote from: coppice on September 23, 2023, 02:36:03 pmTrue, but pure tin plating is unusually susceptible to it, especially if mechanically stressed after plating (like when bending component leads). But indeed, it’s still something that’s not really well-understood.However, the anti-lead-free banshees will cry “tin whiskers” from the rooftops to try and justify their irrational continuation of hating on lead-free.

author: tooki
author_rank: Super Contributor
timestamp: September 23, 2023, 06:32:25 pm
content: Quote from: Monkeh on September 23, 2023, 01:40:07 pmIsn’t it funny how differently people perceive things? To me, the difference is readily obvious, especially when working on heavier joints (like big connectors or shield cans).Just as an example, on Digi-Key, for MG Chemicals rosin-core solders, 60/40 and 63/37 cost the same, and for Kester, every example I looked at, the 60/40 cost more (in some cases, a LOT more) than 63/37. In all examples, always comparing the same diameter, flux type (number) and flux percentage.Given this, it perplexes me that so many people insist on sticking with 60/40. Even if it’s only a tiny bit better, why paymorefor the slightly worse product?!?The reason 60/40 exists isn’t because it’s easier to remember the numbers than 63/37, but because tin costs a lot more than lead, so even just reducing tin’s share by 3% added up to a lot of money for big electronics manufacturers. And of course shops preferred stocking it because it was cheaper, so that’s what most hobbyists got.In the very early days of electronics (like 1920s), people used 50/50 solder, but as things got smaller and more delicate, lower-temperature alloys quickly took over.Quote from: Monkeh on September 23, 2023, 01:40:07 pmI’ve really liked the Felder SN100Ni+ (SN100C using the Fuji patent) solders. The flux is really nice to work with. (There are several big differences I notice between good and bad fluxes, including: effectiveness/activity, spitting (Stannol is awful in this regard), odor, allowable dwell time, and how difficult the flux becomes to remove after soldering, especially with longer dwells.)Conrad.com will ship to the UK for 10 euros.Take a look:https://www.conrad.com/search?ATT_LOV_ALLOY_any=Sn99%2C25Cu0%2C7Ni0%2C05&ATT_NUM_WIRE-DIAMETER_any=0.5%20mm,0.75%20mm&search=Felder%20solder&searchType=regularThose prices are similar to what you’d pay for 63/37 or 60/40 Kester from Digi-Key.Quote from: Monkeh on September 23, 2023, 01:40:07 pmHeh, yeah. I’ve never witnessed that in person, but I’ve seen pictures!!

author: coppice
author_rank: Super Contributor
timestamp: September 23, 2023, 06:51:52 pm
content: Quote from: tooki on September 23, 2023, 05:59:23 pmVery little in metallurgy is well understood. Every time I've had to consult a metallurgist about a real problemI've had this becomes clearer.Quote from: tooki on September 23, 2023, 05:59:23 pmCurrent lead free solders are a PITA. The higher temps melting more stuff. The lower effectiveness of most fluxes. Those factors affecting manufacture cause much greater ire in most people, as they annoying day in and day out.

author: Wolfgang
author_rank: Super Contributor
timestamp: September 23, 2023, 06:54:26 pm
content: Quote from: tooki on September 23, 2023, 05:59:23 pmYou dont need to be a banshee to be risk-averse for, e.g., deep space stuff that must last decades in a hostile environment. Even if leadless solder works, the proof that is will not fail in decades is simply still missing. So - for usual consumer stuff lead free is no problem, if life and death depends on it I would go for classic tin-lead. Whats wrong with that ?

author: Monkeh
author_rank: Super Contributor
timestamp: September 23, 2023, 07:16:45 pm
content: Quote from: tooki on September 23, 2023, 06:32:25 pmBecause I have never paid more for it? In my market, at times I've gone to purchase leaded solder, 63/37 has never been less than 60/40 and rarely even available without going to extremely overpriced 'specialists' (yes please, I'd like to spend £50 + shipping on a 250g roll of solder which offers me nothing meaningful over the £20 roll! Take my money!) or bringing it in from another country, which was expensive and has only become worse.63/37 is better. It just isn't better enough.

author: tooki
author_rank: Super Contributor
timestamp: September 23, 2023, 07:17:30 pm
content: Quote from: coppice on September 23, 2023, 06:51:52 pmBut this is simply untrue. Modern alloys (nickel-germanium doped, i.e. SN100C and the various names it goes by) and good modern fluxes workgreat.Melting stuff is due to bad technique.

author: coppice
author_rank: Super Contributor
timestamp: September 23, 2023, 07:19:57 pm
content: Quote from: tooki on September 23, 2023, 07:17:30 pmThere are no major problems assembling things on a production line, but working on prototypes in the lab.......

author: Monkeh
author_rank: Super Contributor
timestamp: September 23, 2023, 07:20:23 pm
content: Quote from: coppice on September 23, 2023, 06:51:52 pmIf you use Farnell, order yourself a sampler of this stuff when it's back in stock:https://uk.farnell.com/weller/t0051402999/solder-wire-99-3-0-6-0-05-sn-cu/dp/3868987Or, y'know, blow £40 getting anything from Conrad..

author: tooki
author_rank: Super Contributor
timestamp: September 23, 2023, 07:24:02 pm
content: Quote from: Monkeh on September 23, 2023, 07:16:45 pmI’m not talking about historical prices. I’m talking about what one can buynow. Yes, solder has gotten a lot more expensive, but that’s true for leaded solder, too. (Not that I think it really matters for hobby or prototyping use, insofar as solder is a negligible part of the cost of a project or product. Only at large scale is it worth fretting over the cost.)Quote from: Monkeh on September 23, 2023, 07:16:45 pmI agree with that, if it did cost a lot more. Buttodayit doesn’t cost more, and the context where this issue comes up is when people are asking for advicetodayon what solder to buynow. It makes no sense to recommend a more expensive, yet slightly inferior product, and that is what perplexes me.

author: tooki
author_rank: Super Contributor
timestamp: September 23, 2023, 07:29:08 pm
content: Quote from: Monkeh on September 23, 2023, 07:20:23 pmThe Weller solder is not as good as the Felder. There’s a reason I recommended that brand specifically: it’s the best I’ve used so far.

author: tooki
author_rank: Super Contributor
timestamp: September 23, 2023, 07:30:03 pm
content: Quote from: coppice on September 23, 2023, 07:19:57 pmSo… bad technique. It’s possible to do prototypes in the lab with lead-free just fine.

author: Bud
author_rank: Super Contributor
timestamp: September 23, 2023, 07:35:49 pm
content: A few brand name 60/40 that i tried were of better wetting than 63/37. Not sure if that because of the flux. I am sticking to 60/40 at the moment.

author: Monkeh
author_rank: Super Contributor
timestamp: September 23, 2023, 07:38:49 pm
content: Quote from: tooki on September 23, 2023, 07:24:02 pmI advise you get whichever is available without concern as to the two alloys, because the difference isn't worth the time thinking about it. I can't get 63/37 in the sizes and quantities I'd order cheaper than 60/40 today any more than I could last time I bought leaded solder.Quote from: tooki on September 23, 2023, 07:29:08 pmIs it worth the hassle of ordering from Conrad? I sincerely doubt it. There's no sign of €10 shipping and even if there were, that's only part of the excessive cost of ordering from them. There's a reason I recommended the Weller to someone in the UK - because it's available.

author: TimFox
author_rank: Super Contributor
timestamp: September 23, 2023, 08:03:58 pm
content: SN62 (with 2% Ag) is more expensive, is a ternary eutectic with a slightly higher melting point than SN63 binary eutectic, but is a lot shinier and probably stronger.In the current US Mouser listings, all from AIM, for rosin-core wire solder, per (single) 1-pound roll:SN62, 0.050" diam, $53.27SN63, 0.020" diam, $41.82 (no 0.050" listed)SN60, 0.050" diam, $34.62SN60, 0.020" diam, $40.31The price difference between SN60 and SN63 is low, but SN62 is higher.

author: tooki
author_rank: Super Contributor
timestamp: September 23, 2023, 08:21:05 pm
content: Quote from: Monkeh on September 23, 2023, 07:38:49 pmGiven that Weller solder is very expensive (Farnell only selling it in 100g spools maximum), I don’t understand your objection. Get a 500g spool (or two 250g’s) from Conrad and order a few more things to make the shipping worthwhile.The shipping cost was found via a link in the footer.

author: Monkeh
author_rank: Super Contributor
timestamp: September 23, 2023, 08:31:19 pm
content: Quote from: tooki on September 23, 2023, 08:21:05 pmAnd I was linking to a sample set to try, not a 500g spool he may not want to invest in? Or want to make a shopping list just to make it worthwhile to place an order with them?It is expensive, yes - but it works very well. And doesn't end up costing a small fortune just to try.

author: AndyBeez
author_rank: Frequent Contributor
timestamp: September 23, 2023, 08:31:28 pm
content: Any experience of or, opinions on, "low melt" solder? Which is nominally a Bismuth Tin mix that iseutecticat 180C.I recently used an amount of this low melt solder paste on a device's repair. [Mechanic Brand] It just seemed to have a 'life' all of its own.Which kind of reminded me of the liquid alloy the T1000 Terminators are made of

author: tooki
author_rank: Super Contributor
timestamp: September 23, 2023, 10:13:08 pm
content: Quote from: AndyBeez on September 23, 2023, 08:31:28 pmI’ve used ChipQuik brand SnBi solder paste, and it works well. Other than the lower temperature, it behaved much as I am used to solder behaving.What I can’t say is how well it’ll hold up long-term. IIRC SnBi’s mechanical properties are inferior. And it really needs to be kept away from leaded solders, since it apparently can form a mechanically terrible alloy that melts at under 100°C!At my old work, we found the SnBi paste to be handy when working purely with hot air (i.e. when working with insufficient board heating for large and/or heavy boards). But once we got a proper preheater, the need for it really went away.

author: nigelwright7557
author_rank: Frequent Contributor
timestamp: September 23, 2023, 11:05:21 pm
content: Many years ago in early satellites they used lead free solder.To their horror after a few years they were failing.They found the lead free solder started growing whiskers and the whiskers shorted things out.

author: tooki
author_rank: Super Contributor
timestamp: September 24, 2023, 08:53:55 am
content: Quote from: nigelwright7557 on September 23, 2023, 11:05:21 pmCitation needed.The only examples I’ve found of this was with special solders usedwithincomponents, and the whiskers didn’t grow from the solder itself, but from the boundary region at the edge of the solder.

author: AndyBeez
author_rank: Frequent Contributor
timestamp: September 24, 2023, 11:58:33 am
content: Quote from: tooki on September 23, 2023, 10:13:08 pmBack in the day you could buy adissolving spoonfrom British joke shops. Idea was, someone would stir their hot tea with this spoon and WTF! The solid metal spoon has dissolved in the hot water. How is that possibleThe spoons were made from an alloy of Lead and Bismuth. An explicit warning on the side of the packet said, do not drink tea after using! Probably due to the molten blob at the bottom of the cup being a choking hazard - or maybe some Bismuth Cyanide salt?Thinks: I wonder if it is possible to use a 'joke spoon' for low temperature soldering? The joint may not have the conductivity of Silver or the durability of Tin, but it would mean you could repair motherboards with a cup of boiling water. Oh yeah, kinda seen the FAIL already.

author: jmelson
author_rank: Super Contributor
timestamp: September 24, 2023, 03:05:54 pm
content: I have to use lead-free solder as I make commercial gear for export. I pretty much use only lead-free (SAC305) solder paste for the SMT stuff, and use either no-clean or water-soluble SAC305 wire solder for the through-hole connectors. I find the SAC305 wire solder works fine for hand soldering. I do have to turn up the tip temperature a bit as opposed to 63/37 solder, which I often default to on non-commercial projects.Jon

author: davelectronic
author_rank: Frequent Contributor
timestamp: September 24, 2023, 10:45:43 pm
content: Was a while ago know, but I tried lead free with the high silver content, I can't remember the exact content. I bought it from Maplins here in the UK. It was very pleasant to use, wetted very well, shiny nicely shaped joints. The only downside was the price, the reel I bought was over thirty quid. I've gone back to 60/40 now, as I'm not making anything for anyone else. But if you want the best lead free, it's the solder with the highest silver content.

author: Lazarus42
author_rank: Contributor
timestamp: September 28, 2023, 02:40:22 am
content: I came back to soldering after a couple of decades off. I built a simple audio amplifier kit just to get my hand in again.O.M.G! I thought I'd totally lost the ability to tin a wire even!!Ok, it wasn't my old Antex iron but one included in a cheap soldering kit. But I couldn't even get the solder to flow onto a well cleaned, brand new tip! The stuff wouldn't wet anything. It balled up and fell off so many times I was spending longer chopping back wires onto new copper because the insulation was melting as I tried to heat the wire enough for the lead free solder to flow onto the conductor.I'd lost some fingers to sepsis in the two decades I'd had away from electronics so trying to juggle the age old three hands needed problem with new ways to hold the solder, two wires and dab some onto the hot joint was bad enough already but add in solder that won't... erm, solder and it was incredibly frustrating!Straight into town, local electronics shop, had the bloke behind the counter giggling as he got me a roll of solder, heavy on the Pb!The stuff will drive total beginners away before they've started and that will be a terrible thing!Laz(See? Lead hasn't affected me! Anyway, it can't, I'm a helicopter!) 🚁😜

author: analityk
author_rank: Regular Contributor
timestamp: September 28, 2023, 02:31:19 pm
content: It is shock to me read some text where people do not believe in high toxicity of lead and it compounds. What is other facts that you will not agree? Nonsense.Leaded solder is a bit easier to use but some practising make you fluent with lead free solder. I think many problems with LF soldering is caused by inappropriate YouTube guys where people learn hobbyists wrong techniques.Also RoHS doesn't ban lead solder everywhere. Still there are a big class of devices where you can use Pb solder but it has some restrictions ofc. Especially installations, maintenance and disposal of this device shall be executed by technician and this device shall has fixed location for lifetime. There you may use lead in your device.Use solder fluxes. Lubrication is serious business.

author: coppice
author_rank: Super Contributor
timestamp: September 28, 2023, 04:00:18 pm
content: Quote from: analityk on September 28, 2023, 02:31:19 pmWho has suggested that lead is not a toxic material? The question is proportionality. We had vast amounts of lead in our lives, from gasoline to water pipes, and lead solder is a tiny amount of the total. If they instituted a rapid replacement program for all the lead water pipes, that would be meaningful. Lead in solder isn't. A lot of the replacement of lead in components has been substituting the lead for "something not on the RoHS list" regardless of what good or bad health and environmental qualities that has. The US has 100,000 private planes, and almost all of them still run on leaded gasoline. Maybe cleaning that up would do more good than banning lead in solder.

author: HobGoblyn
author_rank: Unknown
timestamp: September 28, 2023, 06:33:55 pm
content: Quote from: metebalci on September 22, 2023, 08:13:39 pmI had lead pipe from water main to house, replaced it about 15 years agoWater is so hard here, it was like it had a coating to protect the water from the lead

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: September 28, 2023, 06:35:45 pm
content: Quote from: analityk on September 28, 2023, 02:31:19 pmLead compounds, yes, metallic lead, not so much - it is notoriously unreactive.

author: TimFox
author_rank: Super Contributor
timestamp: September 28, 2023, 07:48:24 pm
content: Quote from: HobGoblyn on September 28, 2023, 06:33:55 pmIn Chicago, with many leadservicepipes still in service, the local water supply is hard (lots of limestone in this part of the country), and the city water department maintains the water chemistry to preserve the "lime" coating.It can still be a problem if maintenance disturbs the pipes and knocks enough of the coating away to expose lead to the water, or if someone does stupid things to the water system as in Flint, Michigan a few years ago.

author: tooki
author_rank: Super Contributor
timestamp: October 01, 2023, 08:09:55 pm
content: Quote from: Lazarus42 on September 28, 2023, 02:40:22 amGiven that lead-free solder is not a problem whatsoever with a proper soldering iron, I think it's fair to say that the solder alone wasn't to blame here. Yes, lead-free requires slightly higher temperatures. So if your iron is too cold for lead-free, but is just hot enough for leaded, you can easily draw the incorrect conclusion that "lead-free is crap", instead of "my iron is too cold for lead-free".Given how inexpensively one can get a surprisingly decent Chinese soldering station, I don't see the point in even dicking around with an old-fashioned fire stick, which the cheap station will run circles around. It won't have trouble with lead-free.

author: Lazarus42
author_rank: Contributor
timestamp: October 26, 2023, 09:37:43 am
content: Thanks for the reply! Yup, I've already got a Tq2-952 by Quicko. It's a delight to use, fast to temp, a handy temp boost & this one is 220V AC as well as 24V DC so versatile too!The biggest difference though is the Amtech 559 ASM flux! People would've fought over that stuff back on the 80s 😆Cheers Tooki 😎

author: RayRay
author_rank: Frequent Contributor
timestamp: October 26, 2023, 09:58:25 am
content: Quote from: tooki on October 01, 2023, 08:09:55 pmThat's only half the story! Yes, one can melt lead-free solder with a higher temperature. That said, while one can get used to it, leaded solder is still easier to work with and in more ways than one! Leaded solder not only flows better, but is also easier to desolder (which is a major problem with lead-free, which is why it's often needed to add leaded solder to make the process easier) and in general, it's a myth that lead-free solder is healthier than leaded. Only reason why lead-free is mainstream in mass productions is due to EU regulations & it being more "environment friendly" if a faulty product reaches the landfil. Of course each to it's own, but I personally prefer leaded.

author: TimFox
author_rank: Super Contributor
timestamp: October 26, 2023, 02:43:09 pm
content: Yes, I prefer leaded solder as well, but I am now retired from the industry.To anyone starting now, proficiency in the use of unleaded solder will be required at the job.

author: coppice
author_rank: Super Contributor
timestamp: October 26, 2023, 03:09:47 pm
content: Quote from: TimFox on October 26, 2023, 02:43:09 pmNo. What is required is the skill to be always able to get a minion to do the soldering. Minions are the answer to all issues of manual dexterity.

author: tooki
author_rank: Super Contributor
timestamp: October 26, 2023, 04:45:28 pm
content: Quote from: RayRay on October 26, 2023, 09:58:25 amNobody disputes that leaded is easier to work with. With that said, the best lead-free alloys, combined with really good flux, used at the proper temperature, are really, really close to leaded in performance, including flow.“Needing” to add leaded to desolder a lead-free joint simply means you’re struggling to get heat in; a more appropriate iron tip and/or preheating are how you get around that. (This is a situation that can just as easily occur with leaded.)I am fully aware of the shaky reasoning behind the RoHS law. With that said, it’s here, that train has sailedand it’s pointless to whine about lead-free ad infinitum as so many people do. Lead free is here to stay, and people should learn to handle it. It’s not that hard once one stops expending 50% of their energy on the whining when one could spend it on improving their skills…

author: RayRay
author_rank: Frequent Contributor
timestamp: October 26, 2023, 04:57:50 pm
content: Quote from: tooki on October 26, 2023, 04:45:28 pmCan't say I ever had major desoldering issues dealing with purely leaded solder. Regardless, I don't like the way you put it.It's fine if you prefer lead-free solder over leaded for whatever reasons, but you shouldn't put anyone down for having an opposite view. I've used lead-free solder quite a handful of times and my skills are just fine in that department, but I still prefer leaded and it's my goto. Of course that in production lines, a PCB manufactured for EU or international use, it has to be made with 100% lead-free solder, but for personal use (or even paid repair works) it's each to it's own.

author: tooki
author_rank: Super Contributor
timestamp: October 26, 2023, 09:09:14 pm
content: 1. I assure you, when desoldering on a multilayer board with multiple ground planes, leaded solder can be every bit as reticent. Same with big, heavy connectors like coaxial sockets. Or coax sockets on a 4+ layer board.2. Where did you see me say I prefer lead-free? Nowhere, because I didn’t say that. (I use mostly leaded both at work and at home.)What I did say is that the lead-free ship has sailed, and that anyone working in electronics nowadays has no choice but to either retire or become proficient in lead-free.3. Given that I and many others have no trouble working with lead-free when needed, I am convinced that those who whine the loudest about how lead-free is unusable trash are simply people too stubborn to actually give it a try with modern solder and flux, modern equipment, and modern techniques. Rather than learning, they whine. And that gets tiring.

author: tautech
author_rank: Super Contributor
timestamp: October 26, 2023, 10:18:21 pm
content: Modern extremely compact designs with fine traces/small pads of which zero thought is given to simple rework and coupled with LF makes the job more complex than it once was.However gone are the days of socketed IC's so we need get tooled to work with SMD but this miniaturization has worked for and against us.Throw higher temp LF into the mix and fine delicate copper and we're heading for lifted pad disaster unless great care is taken which in many cases is where LF gets a bad rap from.When we attack a PCB with a hotter iron set for LF without preheat we are setting course for bad things to happen, a situation very different from the careful and strict controls used in PCB population/reflow.

author: coppice
author_rank: Super Contributor
timestamp: October 26, 2023, 11:06:56 pm
content: Quote from: tautech on October 26, 2023, 10:18:21 pmEr, no. Designers hate that simple rework has become difficult. It makes development work much harder, and makes fixing things in production much harder. The requirements of many modern products just don't allow design for simple rework with current technologies.

author: tautech
author_rank: Super Contributor
timestamp: October 26, 2023, 11:48:11 pm
content: Quote from: coppice on October 26, 2023, 11:06:56 pmLets define simple SMD rework then.A layout that permits passive removal without hot air (K style tip)Room to snip IC leads for removal without hot air.Room to drag solder in a replacement IC.Minimization of component removal required to provide access to another.All in all full component access from required angles with our tool of the trade, the soldering pencil plus the numerous tip styles we use with them.SMD tweezers, hot air and preheat stations, while all simple devices, are otherwise required for non-simple rework.

author: tooki
author_rank: Super Contributor
timestamp: November 10, 2023, 04:06:53 pm
content: Quote from: Wolfgang on September 23, 2023, 02:06:30 pmLeaded: Kester 44, 63/37Lead-free: Felder SN100Ni+ ISO-Core Ultra-Clear (from Reichelt or Conrad).I haven’t tried Kester lead-free (since it’s much more expensive and I don’t use lead-free much anyway), nor Felder leaded (since it’s impossible to find), but I wouldn’t be surprised if both of them are also good.

author: tooki
author_rank: Super Contributor
timestamp: November 10, 2023, 04:12:10 pm
content: Quote from: tautech on October 26, 2023, 11:48:11 pmMany new components now come only in packages like QFN and BGA that cannot be removed without hot air. The PCB designer has zero control over this.The days where SMD parts all still had leads or exposed contact surfaces are long gone.

author: radiolistener
author_rank: Super Contributor
timestamp: November 10, 2023, 04:30:11 pm
content: We're needs to separate flies and cutlets and don't eat them togetherThere are two incompatible things:1) Lead solder is reliable but can make more harm for environment if we use it in mass production2) Lead-free solder is not reliable (it can be fixed for some degree with new expensive technology, but still has some issues) but make less harm for environmentAnd there is decision to use lead-free solder for mass production. Since many manufacturers don't want it, it requires some kind of dictate in order to enforce them to use lead-free solder for mass production. That's it.There is no need to invent some magic properties and reasons for lead-free, the reason is pretty clean and easy to understand... the key word here is mass production...

author: tooki
author_rank: Super Contributor
timestamp: November 11, 2023, 09:46:41 am
content: Quote from: radiolistener on November 10, 2023, 04:30:11 pmPeople here often claim lead-free is unreliable. But if we exclude the first few years of it (when manufacturers were still learning how to optimize their process parameters, and the solder and flux companies were still developing the best formulas), I haven’t seen any data supporting a drop in long-term reliability of electronics mass-produced with lead-free solder.I think that people often confuse two things:actualreliability andproofof reliability. What I mean by this is that we have decades of documentation and certification of lead solder processes and designs. It’s a proven technology whose strengthsand weaknessesare well understood.Lead-free is much newer, so the history simply doesn’t go back as far. We don’tknowthat lead-free is reliable after 50 years of service, nor do we know that it isn’t. So when high-reliability applications like aerospace and medical stick with leaded, it’s not because they’re saying that theyknowlead-free to be unreliable, but rather that we simply don’t know whether it is reliable or not. It’s possible that it is, in fact, just as reliable for a particular application. Or maybe even better. But until we have long-term reliability data, we can’t say either way.We know that different solder alloys (regardless of whether leaded or lead-free) have different characteristics that affect their reliability for different applications. That’s why even high-reliability applications have always used a variety of solder alloys, some of which are lead-free.My hunch (repeat: hunch, not data) is that other factors will far outweigh the effect of the solder alloy in most situations. A solder joint on a big, heavy component with inadequate mechanical support is going to fracture eventually either way in a high-vibration environment. A board that flexes due to inadequate mechanical support will end up with fine SMD joints (like BGA pins) going bad. A joint reflowed with insufficient heat for the type of solder and flux used may not flow properly. A pin that experiences long-term, significant thermal cycling is going to end up with a broken joint. Etc etc etc. IMHO if your design is so marginal that the solder’s mechanical properties become critical, it’s not a great design.

author: random
author_rank: Newbie
timestamp: January 04, 2024, 06:16:32 am
content: Quote from: metebalci on September 22, 2023, 06:27:37 amI know this is an older post. However, I've been trying to understand what type of soldering iron to purchase for lead free soldering. I've been reading and researching soldering for close to a week now, and don't feel any closer to understanding what to look for in an iron to meet my needs. I am currently a complete newbie at soldering. I have a cheap iron I purchased off Amazon about 8 years ago along with lead free rosin core solder. Only used it to solder the odd wires together and always have had issues getting the solder to melt. I've recently become interested in fixing items on circuit boards and my current iron doesn't seem to be able to melt the solder.I've also noticed that manufacturers are labeling certain irons as "lead free soldering station". This seems to mean that they use the newer more expensive cartridge style tips.metebalci as your original post indicates that you've been using lead free over 5+years.What iron are you using at what temperature?As I can hardly even be called a hobbyist at this point but want to fix a circuit board and think I might enjoy soldering more in the future. What should I look for in an Iron that won't break my bank account?I know there are lots of posts on this forum about irons but I have not found one that discusses the type of solder the individuals are using. As well many of them are quite expensive for not knowing where this will take me.Metebalci as you have 5+ years of experience with lead free I value your thoughts on this.Thanks for any information or insights you are able to provide.

author: tooki
author_rank: Super Contributor
timestamp: January 04, 2024, 03:32:12 pm
content: Quote from: random on January 04, 2024, 06:16:32 amLiterally ignore such claims: a soldering station lets you set the temperature. All else held equal, most lead-free solder requires a temperature (227C, at the joint, not inside the iron’s tip!) about 44C higher than leaded (183C). The temperature at the joint depends not only on the temperature of the tip, but on the tip size and shape, the workpiece, the power of the iron, and how clean everything is.The point is, any soldering station works with lead-free as such.Quote from: random on January 04, 2024, 06:16:32 amFWIW I use an Ersa I-Con nano at home (and at my old work, an I-Con 1, and before that, a JBC T245) and a Pace ST50 w/ TD100 at work, and for all of these, with normal-size tips and typical joints on dual-sided boards and normal small connectors and switches, I mostly use around 300-320C for leaded and 330-340C for lead-free.Small tips will often require higher temperatures because of their inferior heat transfer.Quote from: random on January 04, 2024, 06:16:32 amPeople don’t mention it because it’s not relevant — the things that make a station better for lead-free make it better for leaded, too. Soldering stations generally have ample power reserves that overcome the higher temperature requirements. Only when you are working at the very limits of your station’s capabilities will you see a difference between solder types, but this is simply an issue of power vs. joint. (A soldering station that just barely manages to melt a very large joint with leaded solder will still have no problems at all with small joints with lead-free.)What did change a bit with lead-free was tips, which became plated better to last longer under the higher temperatures. And lead-free accelerated the adoption of cartridge-heater systems, but that would have happened anyway because even with leaded, we use a lot more multilayer boards today than, say, 40 years ago. Not to mention that they’re just nice to work with since they heat up so fast. (No more waiting 1-5 minutes for an iron to heat up.)As for your iron: if it’s not melting anything, it’s either vastly underpowered for the job, and/or there is user error. (The tip must be cleantly tinned with a small pillow of fresh solder as a thermal bridge.)

author: coppice
author_rank: Super Contributor
timestamp: January 04, 2024, 03:55:43 pm
content: Quote from: tooki on January 04, 2024, 03:32:12 pmThis is basically true, but the need to raise the temperature more with lead free solder makes many irons slower to use. The modern fast response irons show their speed benefits a lot more with lead free solder than with lead solder.

author: tooki
author_rank: Super Contributor
timestamp: January 04, 2024, 04:35:06 pm
content: Quote from: coppice on January 04, 2024, 03:55:43 pm“Slower to use”?!? What do you mean?No matter what iron, no matter what solder, in electronics the goal for nearly all joints is to be in and out within about 3 seconds. If your iron (in combination with a given tip) can’t do that at any reasonable temperature setting, it’s not suited to the job, not just “slow” to use, and must not be used.As I see it, the benefits of modern irons are 1. ready to use within seconds, and 2. let you get away with a smaller thermal mass in the tip and heater, allowing for smaller irons. But not speed of soldering operations themselves.

author: coppice
author_rank: Super Contributor
timestamp: January 04, 2024, 05:10:18 pm
content: Quote from: tooki on January 04, 2024, 04:35:06 pmWhy do you think employers are happy to pay for expensive irons for cheap labour to use? Its all about speed. Who can afford to pay people even low hourly rates at 3s a joint? That's an eternity on a production line. With lead solder and a very cheap iron experienced people solder typical through hole and SMD joints at a very high rate with lead solder. Give them lead free solder and they slow down, as it takes time to get to the higher temperatures needed. Give them things like JBC irons and their speed comes back. If the product has numerous high current joints, these modern irons are a big plus for both lead and lead free soldering, but their key benefit is with lead free solder, to recover the productivity loss higher temperatures bring with traditional soldering irons.

author: p.larner
author_rank: Frequent Contributor
timestamp: January 05, 2024, 01:33:19 am
content: i use both,normaly i only use lf in an emergency when i run out of leaded solder,imho the best place for lf is the rubbish bin.

author: the_cake_is_a_lie
author_rank: Contributor
timestamp: January 05, 2024, 03:33:34 am
content: RoHS chips are more expensive when I shop. May as well buy the non-RoHS chips and use leaded solder with minimum required temperature that is cheaper (in US) and easier to work with. The problem with RoHS is politicians with unrelated work experience think kids unscrew their toys and lick the contacts. Lead poisoning is primarily a concern in children due to their small size and development. Too bad they didn't consider the actual bioavailability. Leaded gasoline that people breathed in, that was a problem and I'm sure lobbyists did the Thank You For Smoking treatment to deny.Quote from: Doctorandus_P on September 22, 2023, 03:27:04 pmI had no idea. Much of my interest is maintaining vintage electronics that obviously used leaded solder so I'm glad I'm aware not to mix it.Yeah, maybe there can be advances in non-leaded solder and it can someday be better than leaded at the tradeoff of being far more expensive. Sounds like it's come a long way already. In my small hobbyist world, the ship of lead is still sailing.Sorry for mostly repeating points.

author: p.larner
author_rank: Frequent Contributor
timestamp: January 05, 2024, 03:48:37 am
content: I dont know about in the u/s but in the uk all it seems to have done is push the prices of 60/40 leaded solder thru the roof.

author: peter-h
author_rank: Super Contributor
timestamp: January 05, 2024, 08:03:36 am
content: ROHS is complete total 100% BS. One is asked to certify that one's product does not contain any of about 200 substances (lead being just one) and nobody on earth can possibly be sure of that. So it's all about paperwork. Like Conflict Minerals etc.The old leaded solder went from £5 (500g) to about £40https://www.rapidonline.com/r-tech-856861-solder-wire-60-40-22swg-0-7mm-500g-reel-85-6861At work we have evaluated many samples of unleaded for hand soldering and most are poor. In general a much hotter iron is needed to make them work at all. The best by far is from Almit, which is standard SAC305 but with a decent flux which is actually the biggest problem, and that one is about £70. But it solders as well as the old 60/40 (above).For SMT I use leaded paste for prototyping because it flows far better. For production, SAC305 is used and seems to work ok if the contractor has proper (expensive) equipment.ROHS has cost billions and it's been wasted. No evidence of population health rish due to solder used in electronics.

author: Andy Chee
author_rank: Super Contributor
timestamp: January 05, 2024, 09:41:17 am
content: Quote from: peter-h on January 05, 2024, 08:03:36 amI suppose the health risks come from the disposal of the electronics item, rather than product manufacturing and daily consumer use.Sure, Western countries typically ship their e-waste to poorer countries for recycling, but that doesn't mean manufacturers are absolved of health responsibilities.

author: coppice
author_rank: Super Contributor
timestamp: January 05, 2024, 11:58:06 am
content: Quote from: peter-h on January 05, 2024, 08:03:36 amThese days its not that hard for an equipment maker, although you need to be cautious about the numerous variants of a component, some of which may not be compliant. Most parts are now designed to be RoHS compliant, and you can get a simple statement from the vendor which states they are RoHS compliant. You don't need to go into all the details most of the time. The hard work was with the component makers, who had to do a lot of work to figure out how to make things work well, at decent prices, with compliance. I assume those costs are coming down now that the RoHS compliant market has somewhat stabilised.

author: coppice
author_rank: Super Contributor
timestamp: January 05, 2024, 12:00:41 pm
content: Quote from: Andy Chee on January 05, 2024, 09:41:17 amI think its unclear how much gets shipped and how much goes into local landfills or incinerators. If a small appliance fails it usually just goes into the general household waste. Its only the big stuff that gets separated and treated as e-waste. So, what are the relative sizes of the large appliance and small appliance categories?

author: tooki
author_rank: Super Contributor
timestamp: January 05, 2024, 12:38:31 pm
content: Quote from: coppice on January 04, 2024, 05:10:18 pmOh puh-leez… 🙄One thing I was trying to illustrate, but clearly went right over your head, is that fast response in the iron isn’t the only way to achieve operator speed. The 3 seconds isn’t a target, by the way, it’s a limit.Professional soldering stations have been around, and have been expensive, since long before lead-free, so that argument is clearly nonsense. Employers pay for good equipment because it ensures process compliance and reduces downtime.Yes, lead-free requires more heat. Nobody disputes this. But pumping in that heat quickly does not mandate a cartridge-heater iron. One way is higher tip temperatures. Another way is larger tips. As long as the control loop can keep up, it’s fine. And there’s nothing to indicate that older irons struggled to keep up, unless pushed beyond their limits. (And an iron being pushed beyond its limits is just as possible with a larger joint.) Other solutions include resistance soldering, which I’ve seen videos of in extremely high-speed production.If a production line’s productivity dropped with lead-free until they upgraded their stations, then the stations were inadequate forthose jointswith lead-free solder. But they could just as well have upgraded to a better non-JBC iron with more power. And — and to reiterate, this is my main point — those same “inadequate” stations would still be adequate for other lead-free work with smaller joints. No soldering station is sufficient foralllead-free work (nor for all leaded work), so I vehemently disagree with the original premise that there are special soldering stations for lead-free. There aren’t, there are simply more powerful, more responsive stations, which will improve the situationany timeone is at the thermal limits of their equipment, regardless of whether the source of that need is different solder or larger joints.

author: Andy Chee
author_rank: Super Contributor
timestamp: January 05, 2024, 12:42:26 pm
content: Quote from: coppice on January 05, 2024, 12:00:41 pmAnd just like the RoHS auditing and paperwork, there is now an emerging discipline of documenting e-waste movements. This data may be used by governments to tax tech companies for intentionally manufacturing and profiting from unreliable products with a short consumer lifecycle (unreliability ironically might be attributable to lead-free solder!)

author: tooki
author_rank: Super Contributor
timestamp: January 05, 2024, 12:57:29 pm
content: Quote from: the_cake_is_a_lie on January 05, 2024, 03:33:34 amWhere are you shopping that even carries old non-RoHS chips?!? All the big distributors sold through their non-RoHS inventory years ago.Quote from: the_cake_is_a_lie on January 05, 2024, 03:33:34 amRoHS was never about immediate consumer hazard like kids licking it, but about reducing environmental contamination as a result of disposal. When RoHS was concocted, CRTs were still the overwhelmingly dominant type of large display device, and every CRT TV and computer monitor contains several kilos of lead, thanks to the leaded glass used in the tube itself. The amount of lead in the solder was negligible, all things considered. I don’t think it was obvious that eliminating leadsolderwould a) be as difficult as it was initially, and b) accomplish so little, since CRTs would soon be supplanted anyway.Leaded gasoline was a scourge indeed. The lead was dispersed in the exhaust, depositing all along roads. (While handling leaded gasoline could also introduce the lead to the body, that wasn’t a significant exposure route, generally speaking.)

author: coppice
author_rank: Super Contributor
timestamp: January 05, 2024, 01:17:25 pm
content: Quote from: tooki on January 05, 2024, 12:57:29 pmThe last time I checked there were still quite a few non-RoHS compliant devices being made, for industries where there are exceptions. Some medical applications, for example. That's why I said a few messages back that auditing your product for hazardous materials is pretty straightforward these days, but you do need to be cautious that you are actually using a RoHS compliant variant of a part.

author: tooki
author_rank: Super Contributor
timestamp: January 05, 2024, 01:22:13 pm
content: Quote from: coppice on January 05, 2024, 01:17:25 pmSure, but those parts are typically not stocked by the kinds of distributors that sell to hobbyists (this is the beginners subforum, after all), since those customers are typically going to be ordering directly from the manufacturer.

author: coppice
author_rank: Super Contributor
timestamp: January 05, 2024, 01:31:07 pm
content: Quote from: tooki on January 05, 2024, 01:22:13 pmPeople ordering as hobbyists have even bigger issues with non-RoHS compliant parts than professionals. Much of what is offered to that market was made before RoHS became an issue. Its also stuff so hard to solder, due to long term tarnishing, that its a bigger PITA to solder than lead free parts.

author: coppice
author_rank: Super Contributor
timestamp: January 05, 2024, 01:33:14 pm
content: Quote from: tooki on January 05, 2024, 12:38:31 pmName one expensive soldering station that was getting serious traction in the marketplace before lead free solder was a requirement? A basic Weller or Hakko was the norm pretty much everywhere.

author: tooki
author_rank: Super Contributor
timestamp: January 05, 2024, 02:27:56 pm
content: Quote from: coppice on January 05, 2024, 01:33:14 pmPace, Metcal, fancier Weller, Ersa, Ungar, American Beauty (esp. for resistance soldering), …And I think maybe you forget just how expensive stuff used to be. In 1979, $60 got you a Weller WTCPN, a basic magnestat station with no adjustability, for the equivalent of $225 today. It only went up from there.Pace, for example, has never been cheap, but it’s ubiquitous in military and aerospace (Pace was founded by a military veteran, after all). They’ve been around for over 60 years, and many of their systems cost thousands.The point is, companies back then weren’t using no-name Chinese crap, they were using name-brand equipment that wasn’t cheap.I also think you’re ascribing to lead-freeallof the increased demands in modern soldering, when in fact the work itself has also changed. 40 years ago we didn’t have nearly as many multilayer boards, with their heat-sucking internal layers. We do a lot more SMD, and we do power SMD packages that didn’t even exist then.

author: tooki
author_rank: Super Contributor
timestamp: January 05, 2024, 02:30:23 pm
content: Quote from: coppice on January 05, 2024, 01:31:07 pmHobbyists don’t only order from shitty surplus vendors. Digi-Key has always been for hobbyists (that was what they were founded to do) and they certainly don’t focus on old stock.

author: coppice
author_rank: Super Contributor
timestamp: January 05, 2024, 06:58:23 pm
content: Quote from: tooki on January 05, 2024, 02:27:56 pmHave you lost the plot? I didn't refer to any cheap Chinese tools. I referred to Hakko and Weller. The expensive Wellers just did what the Curie point ones did, but with a knob to set the temperature. The expensive Hakkos were similar. I used to be a mass murderer, but I never saw a Pace iron in the defence industry. Maybe they were just in the US until recently. Everything I've seen built in the defence industry has been built with a Weller Curie point iron. We assembled 8, 16 and 22 layer boards 40 years ago with those irons, through hole and SMD. The only ones that gave any trouble with lead solder were where someone had messed up the thermal lands. Those had to be fixed whether you used the existing irons, or something that could push out more heat, for reliability reasons.Metcal was very niche before lead free solder become the norm. Ungar I am only aware of for cheap and nasty products. Ersa has never seemed special. I had never heard of American Beauty before your post.Note that the need for highly response irons was so small before lead free solder that the RF heated iron was developed and patented by Hakko well before Metcal, but not brought to market until recently, because they couldn't find a market for it.

author: tooki
author_rank: Super Contributor
timestamp: January 05, 2024, 07:41:29 pm
content: Quote from: coppice on January 05, 2024, 06:58:23 pmHey, relax before you have yourself an aneurysm!Well you mentioned Weller and Hakko, but then also seem to think that modern equipment is somehow way more expensive, ignoring that that stuff used to be expensive, too!So… thermally regulated soldering irons regulate temperature. Got it.Pace is ubiquitous (≠ exclusive) in military and aerospace. Certainly in USA, but my old boss worked for years in defense and aerospace here in Switzerland and said that Pace is ubiquitous in military and aerospace here, too.When did Hakko introduce their RF iron? Metcal’s patent was filed in 1986:https://patents.google.com/patent/US4839501A/enAnyhow, I cannot reiterate enough: I am not saying now, and was not saying before, that lead-free does not demand more of a soldering station, all else held equal.But I also vehemently disagree with the claim that there is such a thing as a “lead-free” soldering station. It was every bit as possible to find appropriate equipment and processes before newfangled cartridge-heater irons and the like came out. If your equipment and process is slowing you down, it’s not suited to the task — and that’s every bit as true with leaded solder as with lead-free. THAT is my key point.You started barking at me about employers not buying (supposedly) expensive gear until lead-free, but you never truly answered my question as to HOW lead-free is supposedly slowing things down. You say it takes longer to heat, but that’s simply not true as a blanket statement; match thermal mass and heat flow and you can heat anything as quickly as you want.

author: peter-h
author_rank: Super Contributor
timestamp: January 05, 2024, 08:53:05 pm
content: AIUI it has never been demonstrated that metals from electronics, dumped in a landfill, reaches the food chain, in rich countries or in poor countries.Most lead entering the environment has for very many years been coming from lead used in bulk e.g. car batteries, building materials, etc.Unless forced by customers (whichisgenerally the case today, so actually any manufacturer has no choice about it) I would not use lead-free because there is no advantage whatever. It needs a higher temperature, and unless you pay a lot of money for some high performance flux (Almit) it doesn't flow as well.For SMT, the process is "easier" and with modern machinery the commonly used SAC305, with whatever flux is used (I never looked into it) works well enough. The joints are not shiny like with leaded but they are ok.The thing you still need to watch is components which were not designed for this higher temperature; we are talking about SMT electrolytics in particular and if you get some old stock of these, you can get trouble. Many years ago I had a batch of boards assembled with some Nichicon caps and most of them came back with the tops domed, from gas buildup. It was some old stock of these caps. I doubt anyone will come across this issue today unless they are habitually buying up surplus stocks.I don't see soldering irons being at all relevant. Pace are good irons, sure. I have them at work and at home.

author: coppice
author_rank: Super Contributor
timestamp: January 05, 2024, 09:08:23 pm
content: Quote from: peter-h on January 05, 2024, 08:53:05 pmLead and copper are in an interesting sweet spot. They are not so expensive that we can't use them for applications that need considerable amounts, but they are so expensive we don't waste them. That means they are recycled to an extent we see with very few other materials. Some lead from buildings may get into land fills, although most large chunks - pipes, roofing, etc. - probably get pick up in the waste management chain recycled. However, car batteries have a pretty well established bi-directional supply chain. I doubt there is much lead that gets into landfills from them. Other smaller and less valuable kinds of lead acid battery, such as motorbike batteries, are probably going into landfills in much larger amounts.

author: Jwillis
author_rank: Super Contributor
timestamp: January 05, 2024, 11:01:58 pm
content: A lot of general focus and fear of lead. Over exposure of any metals can cause different health problems. Aluminum have been kinked to Alzheimer's. Copper can cause severe liver damage. Even gold toxicity effects the kidneys and platelet function. Each type of metal having varying health risks at different degrees of toxicity. Handling of most common metals doesn't pose any risk. Toxicity is normally caused by direct ingestion.The biggest problem with lead is the cumulative effects over long term exposure through direct ingestion. Since lead deposits in the liver and kidneys and stays there. Much the same way as mercury. By reducing the amount of exposure the cumulative effects are also reduced. Lead pipes are a problem because of the amount of lead exposure is very high as compared to the small amount of solder used in copper plumbing.This has to due with the total area of lead salts that slough off as the water passes through the pipe. This relationship of lead plumbing and toxicity was first documented in around 130 BC.But we're talking about a lot of lead exposure ingested over a life time and not just a short term handling when using a bit of leaded solder. Wash you hands after use before eating . Don't solder at to high a temperature that can cause the lead to gas off. That bit off smoke produced is the flux contains no lead. Lead needs to reach 900°F/ 4820C to become a gas.Using lead free solder comes with it's own benefits and deficits and is a matter of personal choice for the basic hobbyist. For example I like to use a Indium solder for those plastic package SMD LEDs because of it's very low wetting temperature.Leaded solder for general purpose. Lead free for the high temp applications.But with anything, proper safe handling and usage procedures is important for your health and environment. But keep in mind that being over neurotic isn't healthy either.