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February 1999

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From:
"Stephen R. Gregory" <[log in to unmask]>
Reply To:
TechNet E-Mail Forum.
Date:
Mon, 1 Feb 1999 09:32:54 EST
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In a message dated 2/1/99 1:55:23 AM Pacific Standard Time,
[log in to unmask] writes:

<< Seems to be a hot issue. As a matter of chance I am involved in both
 aspects here. And I face the same problems in both aspects here.

 First  I still work on the reliability of tin-lead solder joints on
 various pad-surfaces since some tests with isolated boards showed a
 somewhat faster growth of cracks in solder joints with pads covered
 with alternative surfaces. But never enough data to make a quantitative
 statement. But I can tell you it is damn hard to get any money for this
 kind of research. Everybody is whining about the lack of test data and
 reliability models. But when it comes to get some money.... Boy,
 discussing with the managers who have to say whether or not you may do
 anything ( e.g. whether or not you get some money ) can really drive
 you nuts...

Boy Guenter, you said a mouthful! It's awful hard for a lot of us getting any
money for normal, everyday production tools, much less anything to do
experimenting with...if I spend money, I'd better have some revenue to show
for it. I did get some first hand experience with the reliability of solder
joints on alternative finishes this weekend, isn't that ironic?

I've got a little Toshiba Portege laptop, I've had it for almost 2-years. It's
just a 486, archaic by some people, but it's got enough grunt to do what I
need it for. It was new back in 1996, so it's coming up on 4-years old.

Anyways, it took a dump this weekend, I would be doing something on it and it
would just power down...boom, no warning, just flat quit. Strange thing, I
could reboot it and it would work fine for hours, or it might quit again
3-minutes after I rebooted, it was totally random.

So I called an "authorized Toshiba service center" to try and find out if by
the symptoms that I described, someone there could maybe tell me what they
think the problem might be. I was told that the power supply was probably
dying very fast, and that it probably had already done enough damage to my
motherboard that it would need replacing as well. Crap! I said, except for the
display, that's the whole darn computer! The tech said yep, but don't feel
bad, I wasn't the only one that was having that problem, they've had a lot of
Toshiba laptops come in with the same problem lately. He said if I was lucky,
I may not have damaged my motherboard, and it wouldn't need to be replaced,
only the power supply at $145 with about $75.00 labor.

     So since my 'pooter isn't in warranty, and me being the curious type, I
opened her up hoping I would stumble across a loose wire or something. One
thing I learned real quick, is that they sure do pack things snuggly in those
little buggers! You can throw everything out that you think you know about how
to get around inside a computer if all you've been into are desktop computers,
laptops are a completely different animal!

I got to poking around and discovered that it was almost like a loose wire, I
had some solder joints come loose on two pins that was on a fine pitch, right-
angle, surface mount connector...the fillets were still attached to the
feet...no bond, or at the very least a very weak one. The connector was the
one that the power supply plugged into. Want to take a guess what the board
finish was? Flash gold...things that make ya go;"hmmmm".

I was able to rework it and saved myself $200 bucks, maybe more, (they
probably would have soaked me for a motherboard if I had taken it in). But
just after I fixed that, I started having problems with my PCMCIA slot, my
'pooter would sometimes see my modem when I plugged it in, sometimes it
didn't...if I re-plugged it a few times, it eventually sees it. I'm almost
counting on it being a solder problem as well because I noticed that the card
receptacle was a fine pitch SMT connector too...(I brought it in with me to
work this morning and will do open keyboard surgery later).

My point being is that my laptop is less than 4-years old and the solder
joints are failing already. I know this wasn't laboratory conditions, and very
unscientific, but I've had 386's that control reflow ovens and have sat on top
of them that are triple that age without so much as a wimper...you all know
how that computer motherboard was finished.

Again, I don't want to sound like I'm against new technology, or better ways
of doing things, but I still don't understand why there's such a BIG push to
eliminate lead soldering.

First I thought it was because of the health hazards, but no, now I hear it's
because of flat pads and it's cheaper...what will the reason be 6-months, or a
year from now?

I've read that lead soldering was first done hundreds and hundreds of years
ago. It's kinda' ironic that one of the reasons that this list was created in
the first place was because of people like us having problems getting the
process of soldering down right, we all needed a resource to be able to share
and communicate so we could learn how to do something that's been done for
hundreds of years. Yet now we're being told that there's new alternative
materials other than lead that are just as good.

So now that many of us are just starting to get the hang of soldering with
lead, there's those that wanna change things on us. It figures, it'll take
another couple of hundred years before we get that down too...

I just think we're moving too quickly on this, and I'm noticing it's starting
to become more and more a political thing too. All I can say is after this
weekends experience with my 'pooter, I'm gonna' have a wary eye on alternative
finishes...

Sorry this was so long...

-Steve Gregory-


One half tells you that your approach is too academic, the
 other half says your plans are not scientific enough. I'm trying the
 third time now. Urged by process engineers of our partner companies.
 Wanna know the answer of the project reviewer? Yes? here it goes:

 >> There is no commercial nor technical evidence that a project
 concerning the reliability of soft solder joints on alternative pad
 surfaces other than HAL is justified. And anyway, all data necessary
 are easily found in literature<<<<

 OK, so much for reliability of solder. The other area I'm working in is
 recycling of electronic waste. Lots of people know, that compared to
 what nasties you find on a assembled PCB's, lead  one of those that
 make us the least trouble.  If one is looking at the technologies
 necessary to extract these substances it becomes clear that the
 extraction of lead is a piece of cake. Because of that, there are hard
 laws coming up in Europe concerning the disposal ( forbidden ) and
 recycling of electronic waste and there are a lot of European projects
 concerning the environmental aspects of electronic waste.   But I can
 tell you it is damn hard.......

 I have some problems in understanding the whole fuss about the removal
 of lead. Anyway electronic waste shouldn't be looked at as waste and
 for sure it doesn't belong into a dump. It would be much cleverer to
 declare it as raw material. You see, one of the main sources of costs
 for recycling of electronic waste is the transport. And just because it
 is declared as hazardous waste and must be transported in transport
 equipment designed for the transport of hazardous waste. Also because
 of the lead in the solder joints. Did someone ever think of the
 transport of electronic equipment before it is out of use? And, coming
 back to ban lead, did ever someone look at the incredible amounts of
 lead coming into our environment by sources other than electronics ( we
 just had a case of high lead contents in game meat due to the lead
 balls used in hunting. Can you imagine how much lead is deposited
 UNCONTROLLED in our countries by means of ammunition? )


 To make the long story short I must say that everybody is lamenting
 about hazardous substances in electronic waste, lots of people talk
 about guesswork when it comes to reliability of solder joints but
 nobody is willing to invest 5 cents to get facts.



 Gee, I think I got a bad morning today.


 Cheers


 Guenter
  >>

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