Lead-free solder?

What kind of solder do you guys use? I can't remember what size I used to pick up.. but I usually just eyed it and grabbed a spool off the shelf without much thought.

Recently I've been thinking I'd rather not inhale any lead fumes.... go figure, huh?

So, can someone recommend a lead-free solder to use? What diameter is good?

Also, do I have to have a specific soldering station that can handle it? I've seen in some descriptions that a particular model wasn't meant for lead-free, yet I don't see why that would make a difference...

Hmmm using RoHS soldering would mean either spending "a lot" in something without lead but with a low fusing temperature or getting a more fragile and with high fusing temperature alloy, not recomended for hobbyists. Also you DON'T want to heat your diodes more than neccesary, and you DON't want solders to crack if thermal expansion doesn't match (sn-pb is more "flexible" and very hard to crack)

The best cheaply available is Sn/Pb 60-40.

The fumes are from the rosin core of the soldering wire. They may contain chloride if they aren't very good. But they don't contain lead, at least in a significant amount to risk a hobbyist's health. If you are planning to solder a lot, you should buy a fume filtering system with active carbon. They are relatively cheap.

It's not good to inhale fumes from virtually any metals anyway. However, like erdabyz said, those fumes you see when you solder are from the rosin in the solder, not vaporized metal. You won't suffer from poisoning so long as you're not intentionally trying to sniff the stuff up.

The RoHS requirement is yet another reason why I'm happy I don't live in Europe. Higher melting point, fragile metal characteristics, cost, etc. are all factors that make non-leaded solder inferior, at least for DIY work. I would go as far as to import leaded solder--illicitly or not--if I lived there.

If you have access to it, I would pick up some leaded eutectic solder, which is 63% tin, 37% lead. It is preferred because it goes directly from solid to liquid, without intermediate states (plastic states) when melted. This is ideal because you don't want your solder being only semi-formed when it solidifies, which weakens the connection.

A friend of mine gave me a spool of Kester Flux "88" 21-gauge solder--a full pound worth--which fits really nicely on the soldering spool holder on my station. I use for my soldering needs; I doubt I'll ever use it all up in my lifetime. Such a spool costs about $23, but it's like a lifetime buy for most peoples' needs.

As previously said, the fumes are from the rosin flux inside the wire, not the metal burning.  Lead burns at 3,000 degrees, the soldering you are doing is way below that temperature wise.   I have actually been reading its more dangerous to breath the non-lead solder fumes than it is the lead based stuff...go figure right?

I have been recommended to use 60/40 rosin core .032" diameter (lead based) solder.  I wanted to go lead based since non-lead based melts at a much higher temp, and in soldering small electronic heat sensitive stuff like this, the lower the temp to melt the solder, the better. (although not horribly low...otherwise it would melt from the normal diode temps. So no Indalloy 117 for this!)

Bionic-Badger said:

If you have access to it, I would pick up some leaded eutectic solder, which is 63% tin, 37% lead.  It is preferred because it goes directly from solid to liquid, without intermediate states (plastic states) when melted.  This is ideal because you don't want your solder being only semi-formed when it solidifies, which weakens the connection.

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At least for me (in Spain) it's easier to get leaded solder than RoHS solder. I pay about... $6-7 (4,5€) for 100 grams of radiel brand 60-40 solder. For me it works very well, and it has a very high quality rosin. You always get shiny rounded solders. I have a spool bought like 1 year ago and it still has enough solder for about other year or more. And I know where to get more (100 meters away from my house).

i use this
http://www.dealextreme.com/details.dx/sku.4643

If you really don't want leaded solder, use indium solder. It costs a fortune (check eBay), but indium is awesome.

-Mark

Thanks for the help guys..

I didn't realize it was the rosin fumes, not the lead.

I think because I'm not going to be doing a LOT of soldering, I'll be fine with the standard solder. It's also a good point to consider that the lead-free takes a higher temperature to melt, which could damage electronic components... don't wanna do that - so thanks for pointing that out as well.

Kloan said:

Thanks for the help guys..

I didn't realize it was the rosin fumes, not the lead.

I think because I'm not going to be doing a LOT of soldering, I'll be fine with the standard solder. It's also a good point to consider that the lead-free takes a higher temperature to melt, which could damage electronic components... don't wanna do that - so thanks for pointing that out as well.

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Just "cheap" PB-free takes higher temperatures. There are indium or bismuth based solders that melt at even lower points than standar solder. But they are $$$ because they use rare metals. If you are concerned about lead, you could wear gloves when soldering and wash your hands properly after. If you play with solder and then you take your hands in your mouth, you'll contaminate with lead (and probably other products).