[Elecraft] OT: News Article on "Tin Whiskers" Ruining Electronics
A recent Associated Press article discusses a topic that's received much attention on this reflector: the negative consequences of environmental restrictions on lead in solder for electronics. The primary concern the article mentions is that tin, when in an alloy absent of lead, promotes the spontaneous growth of tiny "tin whiskers" that can short traces in circuit boards. Failures stemming from whiskers are cited in electronics ranging from consumer items to satellites. The article as it appeared in my local newspaper had a very dramatic photo of whiskers on a tin-plated tuning capacitor. http://www.theworldlink.com/articles/2007/10/06/news/doc4707c03901b23958789121.txt I should note, for newcomers to the reflector, that Elecraft's list of approved solders specifically cautions against using any that are lead free: http://www.elecraft.com/TechNotes/N0SS_SolderNotes/Elecraft-Recommended%20Solders%2009JAN2007.pdf Dick, K0KK ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] OT: News Article on "Tin Whiskers" Ruining Electronics
Typical of news reports, the media seems to concentrate on the sensational. Certainly, the proliferation of throw-away consumer electronics ending up in landfills is a grave concern for adding to the lead content of our environment, and I applaud the efforts to keep that to a minimum. But, consider just how many ham rigs end up in landfills - not many in my opinion. We have many avid collectors of old ham gear and in many cases, boat anchors are a prized possession. Lead-free solders are a real salvation for manufacturers (BTW, the K3 and later K2 boards are RoHS compliant) who can implement the lead-free techniques. For personal soldering, I chose to use my 63/37 alloy solder, and I know that little of it will ever find its way to the landfill. The 'tin-whiskers' problem is one that exists mainly at the chip level. The migration of conductive paths between pins that can be soldered by hand techniques is *not* a problem because the 'whiskers' typically do not extend that far. It is a problem inside the chips where distances are measured in angstroms rather than in fractional inches or millimeters. Bottom line - while you may eventually see this 'tin whiskers' problem resulting in IC failures, it will not be apparent in the soldering that we hams do, even with the fine pitch SMD devices. 73, Don W3FPR Dick & Judy Lamb wrote: A recent Associated Press article discusses a topic that's received much attention on this reflector: the negative consequences of environmental restrictions on lead in solder for electronics. The primary concern the article mentions is that tin, when in an alloy absent of lead, promotes the spontaneous growth of tiny "tin whiskers" that can short traces in circuit boards. Failures stemming from whiskers are cited in electronics ranging from consumer items to satellites. The article as it appeared in my local newspaper had a very dramatic photo of whiskers on a tin-plated tuning capacitor. http://www.theworldlink.com/articles/2007/10/06/news/doc4707c03901b23958789121.txt I should note, for newcomers to the reflector, that Elecraft's list of approved solders specifically cautions against using any that are lead free: ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] OT: News Article on "Tin Whiskers" Ruining Electronics
In a message dated 10/19/07 12:28:43 AM Eastern Daylight Time, [EMAIL PROTECTED] writes: > But, consider just how many ham rigs end up in landfills - not many in > my opinion. Agreed - for two reasons. One is that there simply aren't that many ham rigs around, compared to other electronic devices such as TVs or computers. But the big reason is that we hams try to get as much use out of a piece of equipment as possible, rather than just tossing it in the trash when something newer comes along, or it develops a problem. Even a rig that is judged "not worth fixing" becomes a parts source to keep others going. The computer this was written on is a Dell Dimension XPS R400. It was intercepted on its way to the dumpster a year or so ago. It cost more than a K3-100 when it was new (about 1999?) yet it was considered to be worthless trash in less than a decade. A little work and it does the job. Maybe there's a message there we hams need to spread. 73 de Jim, N2EY ** See what's new at http://www.aol.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] OT: News Article on "Tin Whiskers" Ruining Electronics
At 12:28 AM 10/19/2007, Don Wilhelm wrote... The 'tin-whiskers' problem is one that exists mainly at the chip level. The migration of conductive paths between pins that can be soldered by hand techniques is *not* a problem because the 'whiskers' typically do not extend that far. It is a problem inside the chips where distances are measured in angstroms rather than in fractional inches or millimeters. Not according to NASA studies. They state "Whiskers as long as a few millimeters are not uncommon..." - http://nepp.nasa.gov/whisker/background/index.htm Common through hole IC packages (DIP) have 2.54mm center to center, which means ~1 mm air gap between pins, and that is also a _very_ common hole spacing pattern for discrete components. Here's an example of non-"chip level" failure caused by tin whiskers: http://nepp.nasa.gov/whisker/photos/pom/2004april.htm ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] OT: News Article on "Tin Whiskers" Ruining Electronics
Mike and Jack, My apologies for posting based on my lack of knowledge. Thanks for the educational updates. I certainly am not prone to argue with the NASA research folks. I do recall that it was a big concern inside ICs back in the 1980s and 90s when I was closely associated with the industry and more and more density was being crammed inside those multi-legged critters. I am surprised at the magnitude of inconsistencies and uncertainties still present in the research data. It is very interesting to find that dipping with tin-lead solder appears to inhibit the growth, so those of us using tin-lead solders are actually helping a bit to inhibit the growth - but then we don't re-tin the full length of all the leads on all components either, so there is remaining exposure. So based on reading those articles - my conclusion is that we should continue using the tin-lead solder and discourage the use of lead-free solder for as long as we are able to do that. Since the tin-whisker induced failures seem to take about a year or more to develop, I might consider extended warranty coverage for any expensive electronic devices as more and more of them move to RoHS compliance. This is really a two-edged sword. 73, Don W3FPR Mike S wrote: At 12:28 AM 10/19/2007, Don Wilhelm wrote... The 'tin-whiskers' problem is one that exists mainly at the chip level. The migration of conductive paths between pins that can be soldered by hand techniques is *not* a problem because the 'whiskers' typically do not extend that far. It is a problem inside the chips where distances are measured in angstroms rather than in fractional inches or millimeters. Not according to NASA studies. They state "Whiskers as long as a few millimeters are not uncommon..." - http://nepp.nasa.gov/whisker/background/index.htm Common through hole IC packages (DIP) have 2.54mm center to center, which means ~1 mm air gap between pins, and that is also a _very_ common hole spacing pattern for discrete components. Here's an example of non-"chip level" failure caused by tin whiskers: http://nepp.nasa.gov/whisker/photos/pom/2004april.htm ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] OT: News Article on "Tin Whiskers" Ruining Electronics
main problem with the article is both space programs and military are exempt from being ROHS compliant, so why would lead free solder be in a satellite? Matt KD8DAO ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] OT: News Article on "Tin Whiskers" Ruining Electronics
It is not all in the solder, the problem even for RoHS exemptions is the tin plating on the components. 73, Don W3FPR Matt Palmer wrote: main problem with the article is both space programs and military are exempt from being ROHS compliant, so why would lead free solder be in a satellite? ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: Re: [Elecraft] OT: News Article on "Tin Whiskers" Ruining Electronics
The problem with ROHS compliant soldering is that you must not be able to mix it up with leaded solder. So, a manufacturer has to have one or the other, or separate lines running one each exclusively. So, if the manufacturer wants volume production capability it has to move over to lead-free and dispense with leaded all together in a practical set-up. BTW, I don't think there are any cases of death by poisoning from leaded solder: it's now only a case of environmental issues (ie politics). David G3UNA > > From: "Matt Palmer" <[EMAIL PROTECTED]> > Date: 2007/10/19 Fri PM 04:27:15 BST > To: elecraft@mailman.qth.net > Subject: Re: [Elecraft] OT: News Article on "Tin Whiskers" Ruining Electronics > > main problem with the article is both space programs and military are > exempt from being ROHS compliant, so why would lead free solder be in > a satellite? > > > Matt > KD8DAO > ___ > Elecraft mailing list > Post to: Elecraft@mailman.qth.net > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com > - Email sent from www.virginmedia.com/email Virus-checked using McAfee(R) Software and scanned for spam ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
