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Comment Re:Just a guess.. (Score 1) 173

Bullshit! RoHS isn't silly, it wouldn't apply to spacecraft and you "bible" doesn't negate the actual research that is done on solder alloys after it was printed!

You obviously don't understand alloys and that proportions of different components plus the choice of the components makes a huge difference. You don't understand the reasoning (and research) behind the RoHS and you think an old book triumphs modern research...

It is easy to list things that changes the properties of solders, one example is that bismuth shouldn't be used in standard leaded solder as it can drastically reduce melt temperatures, in a lead free formulation there are not such problems (though an excess of bismuth will make joints fragile).

Bullshit! RoHS isn't silly, it wouldn't apply to spacecraft and you "bible" doesn't negate the actual research that is done on solder alloys after it was printed!

Chill out anger person. The pamphlet showed photograps and photomicrographs of various solders. Lead free solder is not something just thought up then designed by teams of scientists after tin/lead was declared bad. Analysis has gone on for many decades, as pointed out in a cite below. This thing had dozens of images, and the lead free solders of the time looked remarkably like lead free solder of today.

You obviously don't understand alloys and that proportions of different components plus the choice of the components makes a huge difference. You don't understand the reasoning (and research) behind the RoHS and you think an old book triumphs modern research...

Oh anger person, I think maybe less coffee or working out whatever has caused your rage might be in order, because there are one of two choices, you either have anger management issues because going wild over my post is uncalled for, or whatever that is bothering you that causes you to snap at an innocent post needs addressed.

Anyhow, yes, they did have a lot of research back in the day. Especially with solder, due both to it's importance in electronics, but in the different melting points and strength characteristics, as well as the final intended use. A lot of interesting work was going on, in aerospace and space itself, where problems could be pretty critical and life ending. In addition, Mil-Spec had it's own strict requirements due to extreme reliability requirements. In general, Lead free solders were considered inadequate, and many consider them inadequate for the same reasons today. In space, whiskers are a problem aside for their obvious shorting tendencies, but rework isn't likely at all.

If you need a more recent report, here's one from Auburn University: http://aaq.auburn.edu/node/88

Especially important is the following:

"Tin whiskers" were a problem with early electronic solders, and lead was initially added to the alloy in part to eliminate them (http://en.wikipedia.org/wiki/Solder). On July 1, 2006 the European Union Waste Electrical and Electronic Equipment Directive (WEEE) and Restriction of Hazardous Substances Directive (RoHS) came into effect prohibiting the intentional addition of lead to most consumer electronics produced in the EU. Manufacturers in the U.S. may receive tax benefits by reducing the use of lead-based solder. Lead free solders in commercial use may contain tin, copper, silver, bismuth, indium, zinc, antimony, and traces of other metals (http://en.wikipedia.org/wiki/Solder). There is no U.S. legislation presently on the horizon pertaining to lead containing solders. Most of the focus presently on eliminating lead in electronic solders is from European community countries and Japan (www.indium.com/_dynamo/download.php?docid=21). There are many lead free solders exists, but the group comprising tin-silver-copper alloys is considered the mainstream alloy system that will replace tin-lead (www.indium.com/_dynamo/download.php?docid=21).

Is lead free soldering important? It is commonly believed that lead is a highly toxic metal. Some studies show that past uses of lead and lead chemicals in water supply plumbing, paint and gasoline resulted in a measurable increase of lead in the environment and as a consequence, increased blood levels of lead in humans. Paint chip ingestion, mainly by children, resulted in numerous cases of lead poisoning. Consequently the use of lead in these applications has been prohibited for several years. The primary concern now is from groundwater leaching of lead bearing solder in electronic products ultimately disposed in landfills (www.indium.com/_dynamo/download.php?docid=21).

However, this is a very controversial subject. During debate in the 1990’s about the possible dangers of lead soldering, analyses by organizations interested in keeping access to Sn-Pb solder reported that the amount of Pb that might be introduced into the water system from electronics platings and solders posed less of a health hazard then what we already have from arsenic and considered the comparison to children eating lead-based house paint to be non-relevant. There has always been a question around whether this is fueled by cost advantages for high volume production. The horses have left the barn now making the argument mute. This does not necessarily make the pollution argument accurate.

Now, Whether tin/lead, or lead free solder was used, and if whiskers of any sort cause the problem, (even lead can form whiskers) https://en.wikipedia.org/wiki/... the problem would more likely be caused by a breakdown in the conformal coating on the circuit boards, allowing wiskering to occur.

But its all speculation, nothing to get one's knickers in a knot over. Have a beer on me and relax a bit.

Comment Re:Just a guess.. (Score 1) 173

Screwed how? Was it calibrated for the thermocouple effect with that solder or something?

No, what happened was that the lead in regular solder would dissolve the metal plated onto the notch, and it would destroy the connection point. Here is the interior of one of those old scopes http://www.barrytech.com/tektr... You can see the ceramic strips around the middle and top of the scope with the components mounted in between. Seriously weird stuff.

Comment Re:Just a guess.. (Score 2) 173

Lots of stuff is exempt from RoHS. It mostly applies to things you're selling on the open market, i.e. products. You can still buy full-fat lead solder perfectly legally.

I'm actual rather partial to the tin/lead/silver blend for rework. It's quite a bit more expensive than normal eutectic solder, but melts at a lower temperature, which is really handy.

I have multiple types of solder, modern substandard lead free solder, and Tin lead which I use for most things, depending on what the original solder was. Plus a number of silver containing We don't want to mix the types for certain. It is amazing the number of different compositions we have to choose from. I even worked on a couple ancient Tektronix scopes that used special solder that they included inside the case - the components were soldered onto ceramic bars with metal plated notches. You were screwed if you used any other solder.

But the worst solders in my opinion are the lead free, and the more tin, the more likely the whisker problem shows up.

Comment Re:Just a guess.. (Score 1) 173

Why would RoHS directives apply to spaceflight? That would be silly.

Yes it would. Of course, RoHS is silly to begin with. Even more so with more and more electronics being recycled.

Years ago, I came across an old soldering booklet put out by IIRC Kester. Of interest was the contaminants section, with failures and defects. Many of the defects shown were by the presence of the components of modern day lead free solder.

Comment Re:Good news! (Score 1) 157

After parthogenesis is perfected, a few women will go for it. And the rest will go for men as usual, for a variety of reasons: * More fun! * Simpler/cheaper procedure, no need for pills/equipment. A handful one-night stands is all a woman really need from men anyway. * Men are useful for painting walls, fixing car tires, removing snow, carrying stuff from shops, . . . * Alimony

That depends on how many men are going to put up with that shit. Seema a fiar number are dropping out of that mess.

I think it's like this - what is in it for men? That one night stand might get you accused of rape, or certainly you might get nailed for child support intil the offspring graduates college if you being used as an insemination utility is successful. And a man who donates sperm had better understand that he can now be liable for child support. http://www.cnn.com/2014/01/23/...

For those who don't want to read the link, a man who donated sperm to a lesbian couple was successfully sued for child support when the couple fell on financial hard times.

Lest we think this is a isolated case: http://www.canada.com/news/nat...

A retroactive child support suit after 20 years.

And this guy won, but tell me, you gonna donate? http://www.cbsnews.com/news/pa...

So if you are willing to sign your life and fortune and good name away for a piece of ass, have at it. Just go in with both eyes open. Because if she wants your money, she's gonna get it, sepecially if you do it th eold fashioned way.

IOW, you'll get screwed multiple times and ways.

Comment Re:Pleasant surprise (Score 1) 269

And if someone gets a little too frisky with China, and pulls some really dumb move, China owns something like a third of the total foreign held US debt.

And what the fuck are you afraid they are going to do?

That dear sir, depend on what New America does. Now that we are set to reclaim our space at teh top of the heap, we might just need to show China who exactly is boss in this world.

Comment Re:Human females are going to have to do the same (Score 3, Interesting) 157

Because it is so dangerous for a man to get married and have children due to unfair family law. MGTOW. Look it up

While MGTOW is a little interesting, way too much of it is butthurt whining. But the point is taken that an increasing number of men who would make good mates for a woman have done a risk/benefit analysis, and decided that it is not worth it.

And that is kind of a problem. It's a passive avoidance, it isn't illegal. It's like avoiding smoking by not smoking. And as VR and "sex dolls" become more realistic, will only become worse.

What is worse, while stable prudent men decide to pursue their careers and keep their assets, and avoid relationships with females, the jerks and abusers won't change at all.

Comment Re:Pleasant surprise (Score 1) 269

I think their pretty happy with the US's issues with TPP too. Personally, I have some huge issues with TPP of course...but it is a policy to restrict China trade-wise and even rumors of the US abandoning it has allowed China to do various maneuvering.

And if someone gets a little too frisky with China, and pulls some really dumb move, China owns something like a third of the total foreign held US debt. (don't hold me to that exact amount, suffice to say it is a Yuge amount)

Although China needs the US as badly as the US needs China, if we try to bluster our way into something stupid, just calling the debt will make for a rather unpleasant time as the world economy topples.

Comment Re:Catastrophic man-made global warming (Score 1) 269

Aaaaand what percentage of the earths surface is covered by the UK?

That's the "Looked out my window and it was cold this morning - Take that golbal warming douchebags!" theory that he's spouting.

Now that can be of some utility. For instanceI can note that it was a fairly cold winter two years ago here in the Northeast of the US. Okay.

But the part of interest is that the other 15+ winters this century have been warmer than normal. That's a lot more interesting than "soundbite" weather.

If I wanted to play the UK denier's game I would note that I was outside doing yardwork last week in a just jeans and a T-Shirt as the temperature hit 60+ degrees F. But that was weather.

A little more interesting is that during what is statistically the coldest part of the year, it is not going to dip below feezing here for the next week. A little more more interesting, but still weather.

But with that trend continuing for years and years? Now it has become extremely interesting.

The ability of politics to trump science and the laws of physics is remarkable. It's called the "Neener-Neener effect.

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