Solder: leaded or unleaded

Use leaded solder only. No lead solder is inferior and much harder to solder with.
Lead poisoning is no issue as long as you don’t heat lead above 1100+F which is unlikely.
Flux fumes are an issue; try not to suck them in.
A little won’t kill you though.
I’ve done production electronic assembly on and off for over 40 years…

Invest in a good soldering station. You’ll want good hand tools as well. Fine and medium needle nose pliers are essential. Needs dictate tool choices…
Learn about ESD if it applies to what your assembling; loose components if ESD sensitive can be easily destroyed by static electricity…

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Disclaimer: I’m not trying to be antagonistic. This is a place for healthy debate.

Ohh kayy. Unleaded solder melts at a higher temp, which is more difficult to generate/maintain. The higher temp can damage components. Additionally, unleaded solder can produce tin whiskers over time.

I get that leaded solder is easier to use, but just because something is easier does not make it better. It’s possible that 0% of the aerosols generated by leaded soldering contain lead particles (although it’s more likely the low end of a distribution), but you’re still introducing lead to your body by handling it and the environment by using it.

I’ve heard plenty of arguments against unleaded solder at IPC and IEEE events, but they exclusively come from professionals who have been in the industry for a long time. I’ve never heard a single person from a younger generation of EEs advocate for leaded solder.

I can see you fall into that category. I completely respect your opinion, and I value any insights you can provide. Recent and prospective EEs cannot grow in this esoteric industry without help from people with your level of experience. I just wish you would frame it as:

“I prefer leaded solder because X, Y and Z. Try it out and make an informed decision for yourself”

Rather than using your position of experience and authority to assert your views by making claims like


Unleaded solder is also more brittle. I used to work for a military supplier, and we had an exemption for all our electronic products subjected to machine gun vibrations to use leaded solder, because the unleaded joints didn’t hold up properly.


I think the truth is;

Lead free when used properly (correct temperature and style of tip) is just as easy to use as leaded. The problem arrives from beginners / pros using irons or tips not “tuned” for lead free.

That being said, I have lead free I only ever use it when I have to (production boards no for military or aerospace to name a few), as stated most if not all military, aerospace and space applications (think anywhere a fault could cause loss of life) are permitted to continue using leaded solder this is because of;

  • Tin whiskers
  • Vibration cracking
  • Highly acidic flux issues

As an aside, if we ever needed to use solder in any way with any of our implants, we’d go lead free. There are situations where lead solder is not appropriate.


Oh yes! And one of those is definitely inside you! :sweat_smile:

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Interesting: how are connections made if solder isn’t used? Also, isn’t using anything you want a non-issue inside a glass capsule? Or are you referring to issues other than lead seeping into the surrounding tissue?


I think what Amal was saying is they use lead free solder and I presume its incase the capsule ever breaks, better safe than sorry :smiley:

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Lead poisoning is simply not an issue. I worked with lead based industrial paints too as a sand blaster. Lead based paints smell sort of like almonds when you sand it.
No elevated lead levels.
You really have to try really hard to get lead poisoning… just don’t snort it or heat it until it oxidizes to white lead dioxide fumes (+1200F) your iron can’t get that hot!

No lead solders are more brittle and have higher failure rate.
I’m highly skilled at soldering and have used high temp solders for high temp applications. They are a pain to use. Their wetting and flow characteristics suck. It also fouls the iron tip fast especially if you don’t know what you’re doing.

You’re skill set isn’t up to it… without that and a good temp controlled station you’ll most likely fry components and chew up iron tips. There’s absolutely no reason to use no lead solder even on PCBs that use it unless it needs operate in high temperature environments like oil well probes. Trust me you’ll have enough trouble mastering lead based solder… don’t make harder over some nonsense.
Get a descent iron and at a couple small chissle and small cone tips for it. Get Kester 63/37 none acid core ie rosin core or water soluble acid core (needs to be washed off that day). Rosin based residue can be left as is.

You can’t have any type of solder in contact with internal tissue. You nuts?
The body will reject it. More autoimmune diseases out there than you can count; you trigger one it may not stop. Gold, platinum, palladium, some stainless steels and titanium are some of the few metals compatible with human flesh. Tin, copper, silver, bismuth, indium, zinc, antimony, are not!!!

Better use a medical grade encapsulation… not a good idea.

I am 100% certain that @amal means inside the bio glass capsule or other “medical grade encapsulation”. But given there is a chance the shell breaks they would not have lead inside the implant. Pretty sure @amal knows his shit :rofl:




Lead is better than the toxic metals in no lead solders.
There are many Vets that have had inoperable lead fragments for decades.
Lead forms a protective oxide and when alloyed with tin is even more stable.
That said if the glass is breached is going to have to extracted anyway.

Pandering to the lead hype won’t make it safer or easier… more feel good EU bs.
Trust me I know all about their ISO garbage and ludicrous “standards” mostly intented to cripple Japan.
EU been screwing around for decades with laws aimed at leveraging the playing field to their advantage.

Uh huh. You’re a fucking visionary. ROHS is all a government conspiracy.

Small amounts of lead exposure has proven negative health effects. Tin, Copper, and Silver are not readily absorbed by the body and have minimal toxicity. Please don’t peddle that shit here.

This isn’t a good look for your first posts. Leave this thread be for now and we’ll all agree to disagree. If you contribute on other topics maybe we can come back and re-address this.


I’m not going to lie I’m sat here laughing my ass of at it… lead will and does cause lung damage over YEARS of use you can see it in assemble personal and roofers alike. But obviously nothings going to change a certain person’s mind :roll_eyes:

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Oh yawn, a big sister… who needs that shit?
First posts here but I been on the hellholes of forums.
As for lead it extremely hard to absorb unless you ingest it in quantity. Fine vapors of the dioxide being some of the worst or from leaded fuels.
If lead purifies you I got silver amalgamate filling too, oh my.

Cell phones, medical, R&D equipment are exempt. Medical equipment for reliability and cell phones because Philco lobbied for it; they knew the failure rates be sky high. Cells Phones are the biggest leaded throwaways on the planet… to put your greenness in perspective.
Autos are exempt as well as military equipment.

Many pathogenic bacteria and fungus spores can happily sit dormant on unsterilized assembles waiting for a nice wet, warm, iron rich home to become available.
Lead should be the least of your concerns.

Simple Starter Solder Station Setup (& Arduino)

Sounds to me like we are all talking in circles, :recycle: trying to convince others of our understanding and beliefs.

I think all the points of view have been put across, Nobody is going to change anybody else stance.

How about we leave it there, if people have a further questions they can do their own research make their own decisions. :interrobang:

Agree to disagree


I use a kind of spot weld to connect the flex antennas to chips, same as the robots that make full size ISO cards use… zero solder. In the glass tubes, there’s a number of methods including flip chip to COB… but sometimes a very small amount of tin solder is used, then fully encapsulated in med grade resin, inside the glass.


This is… hard to believe. How do you know you have no elevated lead levels? How exactly did you test this? Also, it doesn’t take acute toxicity to drastically effect your brain, which is the primary issue with lead… chronic exposure, even at a low level, has a subtle but detectable effect on cognitive abilities, even in adults. In fact, a man who I can’t remember and Google has failed to find for me spent 30+ years fighting to ban leaded gasoline because he was tracking an overall lowering of IQs across the US as more and more cars were driven throughout the cities and other congested areas. Much more acute effects were seen when leaded gas was first being handled in the 1920s…


So was this before the spot welding or is that the: