non-toxic solder and flux

[Steve Jones]

it sounds good, though I have heard that for reworking there can be issues with mixing the 2 kinds of solder together, so it may be only good for new projects. I am looking forward to getting away from those flux fumes though.

 

[NewYorkDave]

"Lead fumes?"

If your soldering iron is hot enough to vaporize lead, then it's time to stop using a welding gun for soldering.

Wash your hands before you eat that sandwich or smoke that cigarette. Wait, if you're the kind of person who worries about solder fumes, then you probably don't smoke.

Don't lean over the work and suck in the flux fumes if you can help it.

I've been soldering for years and my bloodwork still comes back as normal. You guys must be pretty new at this if the smell of flux still bothers you :wink:

 

[rlaury]

One thing I found out about the water based flux and no lead solder just this week is, Denatured alcohol won't clean it off. and It is somewhat conductive. It caused creepage between connector pins and caused several hundred boards to fail our UL HiPot test. It seems like the silver was being absorbed by the flux and the denatured alcohol
aided this somehow in that process. I measured 128 ohms across 2 pins on several hundred boards that should have read several megohms. Washed them with water,
hot air dried them, problem solved.

Just a heads up.

RonL

 

[MikoKensington]

I was building one of Joe Malone's power supplies the other day. I thought I'd try some lead free silver solder stuff from the Shack. It tinned the lead nicely, but getting it to play nice the components and board was next to impossible. So I broke out that nasty Oatley solder and made my life easier. Until I get the lung goblins 30 years from now.

 

[SonsOfThunder]

[quote author="rlaury"]One thing I found out about the water based flux...Denatured alcohol won't clean it off.[/quote] i find that quite surprising as I have yet to see a flux that would not clean off with alcohol and a little scrub.

It is somewhat conductive.

Not surprising at all. I have seen audio amps with high THD that would not go away, wash the PCB, THD comes waaaay down. I've seen this more with "no-clean" flux.

The melting point; 423 degrees F for IA-423 lead-free solder
as opposed to approx. 375 degrees F for Kester leaded silver solder

For DIY, this might be just fine...for production quantities this will be a nightmare with increased component failures! But this comparison is not generally valid as most of us don't use silver solder. From the Kester website the normal 60/40 is 361 to 374 so that could be as much as 62 degrees higher.

Thanks for the info!
Charlie

 

[Category 5]

I have a roll of solder (don't know where I got it, it's just THERE) that is 96% tin and 4% antimony. It uses regular rosin based flux, but says right on it "Lead Free Solder".

What do you guys think of this stuff...at least regarding the lead issue.

My current fave is 63/37 .20 diameter "no clean" type. It's so thin it makes it very easy to solder small areas of the PCB (like those Grayhill 12 position switch pins).

Shane

 

[kato]

[quote author="Category 5"]
My current fave is 63/37 .20 diameter "no clean" type. It's so thin it makes it very easy to solder small areas of the PCB (like those Grayhill 12 position switch pins).
[/quote]

You mean .02 diameter, right?

I've been thinking of trying the "no-clean" type of solder but I noticed it only contains about 1% flux as opposed to the 3% flux in other solders. Do you find that no-clean solder adheres just as well as regular solder?

Thanks, Kato

 

[Gus]

One of the reasons lead is in solder is because of the "tin pest" lead prevents tin wiskers from forming. Metal wiskers can be a major problem.

Nasa has a page about metal wiskers IIRC.

Google tin pest and metal wiskers.

edit

http://ap.pennnet.com/Articles/Article_Display.cfm?Section=Articles&Subsection=Display&ARTICLE_ID=216209

http://materials.open.ac.uk/srg/srg_tp.htm

http://dwb.unl.edu/Teacher/NSF/C10/C10Links/chemistry.about.com/library/weekly/aa040300a.htm

http://en.wikipedia.org/wiki/Whisker_(metallurgy)

http://www.twi.co.uk/j32k/unprotected/band_1/elec_nl11.html