Posted on 01/28/2015 9:11:12 AM PST by dennisw
Almost ever electronic device made today except some for the military have solder joints that contain no lead. This is an effort to save our groundwater and our public health. The fact that the lead has been generally replaced with silver or bismuth, both of which are actually greater health risks than lead, well well leave that one for Ralph Nader. The longer-term trend is toward all-tin connections, anyway, but they dont work very well, either.
Costs have gone up for computers with lead-free solder, mean time between failures (MTBF) has gone down (in this case down is bad) and reliability has suffered. Since we dont fix things anymore, its hard to say whether your gizmo failed because of bad solder or not, but the problem is becoming worse as a greater percentage of total circuits in use have lead-free solder. The military and NASA were especially concerned, so they generally operate under waivers allowing lead solder in the gear on which our space program or national security supposedly depend.
If your PC lives long enough it will eventually be killed by what are called tin whiskers single crystals that mysteriously grow from pure tin joints but not generally from tin-lead solder joints. Nobody knows how or why these whiskers grow and nobody knows how to stop them, except through the use of lead solder. Whiskers can start growing in a decade or a year or a day after manufacture. They can grow at up to nine millimeters per year. They grow in any atmosphere including a pure vacuum. They grow in any humidity condition. They just grow. And when they get long enough they either touch another joint, shorting out one or more connections, or they vaporize in a flash, creating a little plasma cloud
Thank you for the education, that’s all good to know.
I’m not an expert in solder by any stretch and only got into soldering electronics 10 years ago when I started with radio. I’ve replaced a good number of caps in those years since they seem to be the most common component to die in electronics. I’m definitely a neophyte, but I love my hardware; and I’m not afraid to try to fix it when it’s not working.
The smoke gets out?
Most high availability computing environments call for regular shut down and vacuum out of computer components for this very reason. Home users should do this once per year to extend the life of their equipment.
Nothing Gillette cannot solve with a proper infusion of R&D capital.
PFL
Why? It's none of your bismuth.
Funny that the feds make you disclose the potential for lead paint in any home built in 1978 or prior, but nothing is mentioned about the potential for lead solder in your water pipes. Meh. I'm in the process of buying a house built in 1969, with copper pipes. Am I worried? No. Lead paint? Grew up with it, lead solder, drank all the water I drank as a kid from pipes soldered with it. I'm okay.
So am I.
Me, too.
Don't forget me...
As we learned from Hayek in the Road to Surfdom, the government by planners does not work because you can plan and mandate all you want but the outcome will be flawed as planners can’t account for reality.
Central planning works with finite goals and mandates and cannot take into account the reality of the market, the reality of God’s universe and the reality and variety of humanity.
On all my surface mount designs I used SAC, Tin, solver, copper. There have been several instances where I had to spec PbSn, but at that time it would still be considered RoHS. SAC works fine under most conditions.
The main problem I had was things that relied on their solder connections as a mechanical mount point, such as DC-DC power supply modules, daughter boards and large pig tailed cable bundles soldered directly onto a PCB board.
Tin will crack and slag and if there is nickel in there, then you definitely can get whiskers. Plus the angle of repose is shallow which contributes cracking and conductivity problems.
My first CNC machine was built in 1978. It was a massive collection of relays and cards easily 20 times the size of a modern day controller. The boards were soldered with good ol’ lead. When a component burned out it was super easy to melt the solder and put a new replacement part. I finally sold the machine because I outgrew it but I know for a fact it still works to this day.
My newer machine is all solid state with Al Gore approved lead free solder. I have had 2 control cards blow up, and cost $3000 each, within 5 years. I don’t know if they are related to the new dolphin safe solder but I would venture they are.
Heck, just look at the Voyager spacecraft. 40 years and billions of miles away and it’s still kicking.
This may become very critical in expensive camera gear from what I read.
Google “bad chinese caps” or similar. There was a 2-3 year period of time (accordingly; how long it took for the problem to surface) when the quality of electrolytics in particular from several mfrs coming from China just reeked. They failed all over the place, in vast swarms, at maybe 30% of their expected life. It was maybe half a dozen brands (out of probably 100 brands) but of course since they were the cheapest brands and very widely distributed, they were used in gargantuan quantities.
There’s a lesson in there, somewhere.
Good numbers of elect techs have made their livings over the last 5 years over these caps. The failure became so common on LED screens (which of course, got much much cheaper a few years ago and thus as you’d imagine prolifereated in mass qtys) that there are “re-cap” kits sold all over ebay, by multiple vendors. Very commonly, you replace half a dozen of those bad caps in the power supply and you are good to go for another 5 years. $12-$15 or so. Of course it is tricky as hell to get those screens open and juggle them to make the replacement. But it can be done and the success rate is >80%.
I am not sure I would get so philosophical! You use cheap crap in your builds and the results are predictable. The Chinese probably just worked to get .001 cent cost reduction into each cap and found the dead nuts bottom of what would work.
A couple of good links from the NASA program I found on Ken Rockwell’s camera site:
Page 41 starts into detail at this pdf:
http://nepp.nasa.gov/whisker/reference/tech_papers/2011-kostic-pb-free.pdf
and this site:
http://nepp.nasa.gov/whisker/
I have a Kenwood TS-450SAT that seems to be holding up just fine. Did a little touch-up of a couple of solder joints that might have become problematic at some point. For a piece of early 90s gear, that’s not bad.
I have a few 1 pound rolls of 50/50, but close to 40 of the 1 pound rolls of lead free.
I stocked up when prices started getting high.
While assembling this general FCC nuisance, he apparently attached a cap backwards... and it was a fairly large can-type capacitor (I'm not an electronics guy, that's my technical terminology). anyway, you know what happened when he applied power. It blew, and proceeded to spew a stream of black oozing mess on the wall behind the counter while the entire house filled with a stinky smoke.
Well, it got "mostly" cleaned up and the wall repainted minus one small circle about 2" in diameter. My mom insisted it be left there and to this day, when he drags something into the house that doesn't belong there, she points to that spot on the wall, still unpainted to remind him of his poor judgement. I have to laugh, it is pretty funny and I don't even know why I felt compelled to tell this story. It just amuses me to no end.
I remember those Chinese capacitor problems.... Even today you see mother boards being touted as having all Japanese made capacitors
my three year old sony viao screen blanked out and i attributed it to the solder on the video chip to board. there are videos about resoldering these chips but i haven’t tried it yet.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.