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I have been a hobbyist solderer for about 6 years now, and my skills are very proficient. I have always used lead solder because my experience with lead free solder is awful. But I'm going to college in a few months and I just upgraded to a very nice digital soldering gun because I am making and selling aviation cables online. I am hoping to expand my little cable business in college and if I am going to be soldering often I would like to get away from lead solder.

Are there lead free solders that can be used as easily as lead solder, and if so, if there really any health benefit from lead free solder? Are the fumes from solder toxic, and does lead free solder solve that problem?

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    \$\begingroup\$ One of many Lead-free solder problem documents: <aviationtoday.com/av/commercial/…> \$\endgroup\$
    – Dwayne Reid
    Jul 6, 2015 at 3:06
  • \$\begingroup\$ As someone working in avionics, I know the look you would get from customers if you told them you were using lead free solder :) \$\endgroup\$
    – Peter Smith
    Aug 20, 2016 at 16:17

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Use leaded solder if you can. It is easier to work with, requires lower temperatures, and there are less quality issues with the joints. The only reason to use lead-free solder is if it is not allowed in your jurisdiction or you are want to sell soldered goods someplace (like Europe) where this is forbidden for practical purposes.

No, lead in solder doesn't pose more of a health risk to you when soldering. The vapor pressure of lead is so low that there just aren't significant numbers of lead molecules in the air as a result of soldering. The predominant health danger from soldering is inhaling the vaporized flux. This is made more dangerous by lead-free solder since the temperature required for a good joint is higher. Even that is a small issue compared to different types of fluxes. If you are worried about this, use a fume extractor. In any case, avoid breathing the immediate vapors from soldering, whether leaded or lead-free and regardless of the type of flux.

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  • \$\begingroup\$ Flux is just organic carbon-based stuff anyway; unless there are some chlorinated benzene rings in there that bio-accumulate, it's probably even good for you in small doses, like the roasted malt that goes into beer, dark coffee, or that tasty burnt crust on steaks. \$\endgroup\$
    – Kaz
    May 27, 2013 at 23:26
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    \$\begingroup\$ benzopyren - C20H12 - is hazardous but not chlorinated. See also purexus.com/fume-extraction/examples-of-hazardous-fumes \$\endgroup\$
    – david
    May 28, 2013 at 2:57
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    \$\begingroup\$ @Kaz: Just because something is organic or "carbon based" without chlorine doesn't make is safe for humans to breath. Just the particles alone can cause trouble. Think of black lung or "coal miners disease". There are many many poisonous carbon compounds that don't contain chlorine, like hydrogen cyanide gas, methanol, carbon monoxide, etc, etc, etc. \$\endgroup\$
    – Olin Lathrop
    May 28, 2013 at 12:31
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    \$\begingroup\$ Cyanide is carbon based too. Hydrogen and nitrogen.Therefore organic, and since the gases are extracted from air and water, they're Free-Range too. Enjoy!! \$\endgroup\$
    – user80427
    Jul 6, 2015 at 0:40
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    \$\begingroup\$ Every piece of electronics will some day be discarded, and using lead means that lead will end up in the environment. It also means more lead will be mined, when it doesn't need to be mined. The mental health problems and developmental damage caused by increased lead in the environment is a scientific fact on the level of Evolution or Climate Change. \$\endgroup\$
    – don bright
    Aug 4, 2015 at 2:58
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Lead free solder can be really hard to work with.

If you buy a name brand solder, which isn't 99%Sn and 1%Cu then it will be similar to leaded. Personally I use 95%Sn 4%Ag and 1%Cu. You will need a bit higher temperature on your iron. I have a Hakko FX888-D and I use 310C° for lead free and 265 C° for leaded.

Lead free alloys will eat away your tip a bit faster, and you will need to clean the tip more often (oxide forms much faster on the solder on the tip). At first I hesitated to switch, my first'experience was with a cheapa$$ soldering iron (directly to mains one) and cheap "Lead Free" solder. Lead free solder is a bit more expensive (I payed like 14€ for 100 g of lead free solder, diameter 0,5 mm, stannol brand).

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    \$\begingroup\$ 0.5 mm seems narrow and that is good. Since lead-free solder has a higher melting point it can help to get the narrowest gauge you can find. Feeding in a narrow solder wire will have less effect on the temperature at the point of contact. \$\endgroup\$
    – H2ONaCl
    Nov 14, 2019 at 23:15
  • \$\begingroup\$ Thank you for the helpful pointer to look at solder with silver replacing the lead. Just to save anyone else some time, a keyword that's useful for finding a common type is "SAC305", which is short for Sn-Ag-Cu with 3% Ag (silver) and 0.5% Cu (copper). \$\endgroup\$
    – Jon Colverson
    Dec 15, 2022 at 17:15

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