60/40 vs. 63/37 Solder
in [Basics]
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From: Jeff Liebermann on 17 Jul 2010 01:18 On Fri, 16 Jul 2010 20:14:45 -0400, "Michael A. Terrell" <mike.terrell(a)earthlink.net> wrote: >Jeff Liebermann wrote: >> I have some rolls of solder around the shop that are not well labeled >> or identified. Rather than risk leaving corrosive flux on a board, I >> prefer to clean most everything. > I just tossed solder like that into my solder pot. Right. Great idea. I did that once and regretted it. I tossed most of a 1 lb roll of Ersin 362 (62/38) rosin core solder into the wire lead tinning solder pot. The roll had gotten splattered with acid and was leaking flux. The result was a large cloud of noxious smog, as all the rosin simultaneously went up in smoke. You've seen the smoke produced during soldering. Now multiply that by a few thousand times. If it had set off the smoke alarm, I would have really been in trouble. I don't know the correct way to recycle and remelt old solder. Whatever it is, should probably be done outdoors. -- # Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060 # 831-336-2558 # http://802.11junk.com jeffl(a)cruzio.com # http://www.LearnByDestroying.com AE6KS
From: Jasen Betts on 17 Jul 2010 09:00 On 2010-07-16, Jeff Liebermann <jeffl(a)cruzio.com> wrote: > On Thu, 15 Jul 2010 13:06:03 -0700, dplatt(a)radagast.org (Dave Platt) > wrote: > >> ><http://en.wikipedia.org/wiki/Solder> > This got my attention: > Some alloys, namely of lead and to some degree tin, contain small > but significant amounts of radioisotope impurities. The > radioisotopes undergoing alpha decay are a concern due to their > tendency to cause soft errors. Polonium-210 is especially > problematic; lead-210 beta decays to bismuth-210 which then beta > decays to polonium-210, an intense emitter of alpha particles. > Uranium-238 and thorium-232 are other significant contaminants of > lead containing alloys. > Oh swell.... something else to worry about. sounds like bullshit, alpha particles aren't energetic enough to get even 1/10 of the way through the encapsulation on a RAM chip. fraction of the --- news://freenews.netfront.net/ - complaints: news(a)netfront.net ---
From: William Sommerwerck on 17 Jul 2010 09:28 >> <http://en.wikipedia.org/wiki/Solder> >> This got my attention: >> Some alloys, namely of lead and to some degree tin, contain small >> but significant amounts of radioisotope impurities. The >> radioisotopes undergoing alpha decay are a concern due to their >> tendency to cause soft errors. Polonium-210 is especially >> problematic; lead-210 beta decays to bismuth-210 which then beta >> decays to polonium-210, an intense emitter of alpha particles. >> Uranium-238 and thorium-232 are other significant contaminants of >> lead containing alloys. >> Oh swell.... something else to worry about. > sounds like bullshit, alpha particles aren't energetic enough to get > even 1/10 of the way through the encapsulation on a RAM chip. Correct. The original writer was probably confused by the fact that the materials ceramic ICs are made of can contain radioactive materials that can cause errors.
From: krw on 17 Jul 2010 11:04 On Sat, 17 Jul 2010 06:28:08 -0700, "William Sommerwerck" <grizzledgeezer(a)comcast.net> wrote: >>> <http://en.wikipedia.org/wiki/Solder> >>> This got my attention: >>> Some alloys, namely of lead and to some degree tin, contain small >>> but significant amounts of radioisotope impurities. The >>> radioisotopes undergoing alpha decay are a concern due to their >>> tendency to cause soft errors. Polonium-210 is especially >>> problematic; lead-210 beta decays to bismuth-210 which then beta >>> decays to polonium-210, an intense emitter of alpha particles. >>> Uranium-238 and thorium-232 are other significant contaminants of >>> lead containing alloys. >>> Oh swell.... something else to worry about. > >> sounds like bullshit, alpha particles aren't energetic enough to get >> even 1/10 of the way through the encapsulation on a RAM chip. > >Correct. The original writer was probably confused by the fact that the >materials ceramic ICs are made of can contain radioactive materials that can >cause errors. Happened in plastic too. Intel once helped the problem along by using Kr instead of Ar, IIRC, in a hermaticity test. Battleship steel has a lot of uses, too, since it was forged before the first atmospheric tests.
From: Smitty Two on 17 Jul 2010 13:15
In article <i1ovm1$ccb$1(a)news.eternal-september.org>, "William Sommerwerck" <grizzledgeezer(a)comcast.net> wrote: > >>>> The only reason 60/40 was ever manufactured in the first place is > >>>> that tin is more expensive than lead, so 63/37 solder costs more. > > >>> Cite, please? (and I don't mean a link to commodity prices) > > >> I can only cite "common sense". 63/37 has always been > >> more-expensive than 60/40. > > > Then you can't substantiate your contention that 60/40 was THE > > worldwide standard for tens of years just because it was a few pennies > > cheaper per pound? That is the statement of yours with which I take issue. > > I have no objection to your objection. > > However, 60/40 was never, ever, "a few pennies per pound" cheaper than > 63/37. For the last 30 years, the price of eutectic solder has been > sufficiently higher to make one think twice before buying it. The last time > I purchased solder, I decided that a one-pound roll of Kester 44 would last > the rest of my life, and I splurged. (At this point in my life, my > prediction is coming true. I rarely solder any more. If I drop dead, someone > digging through the junk will find a pleasant surprise. Assuming they know > what 63/37 is.) > > I just checked Parts Express, and a 1# roll of Kester 44 60/40 is $22.23. > 63/37 is $26.85. That's a $4.62 difference, almost 21% more -- hardly > "pennies per pound". When I bought the same product some years back, my > memory is that the price was around $7.50 for the 60/40, $9 for the 63/37. > Even that wasn't "pennies per pound". > > Businesses almost always try to cut every corner they can. If you think your > solderers -- or soldering machines -- are doing a good job, you might prefer > to buy the less-expensive 60/40. > William, Parts Express sells to hobbyists. Their prices are meaningless as a reference. I buy solder, as I have for 25 years, from industrial suppliers. Since you didn't state either the diameter or the core, (and diameter can make a huge difference in price) I looked up your comparison rolls on Parts Express. I see you referred to Kester 44 with a 66 core and at .031 diameter. To compare apples to apples, I called my supplier yesterday for current pricing: 63/37, $13.80/lb. 60/40, $13.30/lb. I also asked how many people were buying 60/40, and she confirmed that well over 90% of customers use 63/37. 1. You're paying nosebleed prices whichever formula you buy. 2. The cost difference is indeed pennies when purchased from real supply houses 3. Regardless of the cost difference, 63/37 *is* the standard now, as it has been for 20 years. 4. Based on #3 above, your assertion that companies will cut corners anyway they can is false. 5. Therefore, my contention that the widespread switch was made due to improved performance of 63/37 seems to be the only logical conclusion. Now, you said that 63/37 eutectic nature was known 50 years ago. That may or may not be true, but what is true is that the widespread industrial changeover happened much more recently, about 20 years ago. |