Hmm ; Steve ; you'll get me inferiority complex if you'll go on like this
for much longer :
Feelin on top hey ? Did you hear bout' workin' smarter ; not harder ? (The
bottom I mean) ;
confused like the Austin's with little engines ? :
We did in about US $ 100K + in this 5cents worth of getting facts ; through
the IPC-SM-785 rig which Werner was kind enough (without gettin' a cent so
far for it ; poor chap) to help us to set up .
The results (on NiAu; d) which I still owe David were so good I still repeat
them and counter verify with all sorts of shear interpolations to believe it
;
apart from that I hope David will pepper you up on that meeting as he must
have tones of references with considerate sums behind them .
Agree the early versions of SMD cons without PTH anchors (FIH) are (still)
on the naive design side ; especially considering the constant vibrations of
cables attached ;
or similarly frequented sockets .Is this free negative toshiba advertising
like your BGA saga to be continued ?
And true again ; 100um of 24 carat jewelry work will not pay off the field
reputation ;
agree the hasl you can treat with stone axe without making mistakes ; but as
few times said here :
don't forget some of us are not so lucky to have only straight forward
soldering requirements from the cards ;
I'd love to sit on tin forever if I could ; just the vetability is an utter
delight I dream about co
Being ex you should know better the technology IS the card in most
commercial or other disputes .
It's still much cheaper and reliable trot the horse with a lance ; until you
get shot down with tomahawk of second kind ; third on the way
See you mate
willing nobody
> ----------
> From: Stephen R. Gregory[SMTP:[log in to unmask]]
> Sent: Tuesday, 2 February 1999 1:32
> To: [log in to unmask]
> Subject: Re: [TN] Lead removal
>
> 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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