Nope, it does not help at all ; sorry ,
while the know-how galleries are choking on coffee reading this kind of
"help",
plenty of innocent souls can actually take this "common" sense
proclamations as "logical" .
Insertion problems checks ?, cyanide?, gold by ounces?, holly ghost, is
this 1.4.00 ???
That is 4.1.00, for Yanks .
Ron ;
you have not much luck, obviously none of fab eng's (discounting the
cyanide) are biting .
Mind you a lot of other sitting ducks told me in my life the more the
better .
Saying that,however, i remember Bev in nortel's life have had good service
from ducks
(unlike the below 'advice')
Whenever I got anything with more than 1.5umAu (as recomended limit by
ITRI)to solder on;
i simply scraped the boards AND the supplier (internal limit here 0.8umAu
over Ni for solder).
I know it hurts on 4+layers ; but the cost and strains of reversals is not
worth it in my opinion;
that is if you can get reliable boards remade (Hitech-Koyden in Korea ships
within 3-5 days)fast&cheap.
If you're really straped in hot place and can't scrap ;
check it with Rudy or get bee line to Moon man (busy now),
but it's likely they tell you much of same : too costly to guarantine for
realiable smd's .
If it's pth ; in absolute extremes (after hours that is, no soul around) i
did wash gold off by running over wave and knocking the inhole liquidus off
by flipping the edge of board over a piece of wood within 1 second after
wave edge pass.
Absolutely do not offer this as an advice ; just describing my desperate
practical actions within certain contexts,
takes loads of bad attitude and good aptitude (practice)
mail me off line with/for details if yo still stuck .
paul
ps
Going through the maths & reasons with Tim :
there is some 40u" in 1um .
that means our tight 0.8um limit is 32u" ;
just about ideal for soldering .
up to 1um we get on IMMERSION easily (=up to 40u").
but you say electroplate ?
Agree with Tim ; what do you do ?
From your past correspondence i can see it's solder, likely pth as well,
if yo would have 6-10u" in specs , = 0.15-25um ; that would be not only
lowest spec for soldering ever seen,
that would be wrong as well as the Au barrier would not hold cover to
prevent Ni oxide (god help yo than);
you could not stock the boards for much longer than weeks .
Beside, on QC line ; who would measure you commercially 6-10u" window ?
I have commercial resolution limit 0.3um, = 12u" ; anything below this
resolution check would cost me a fortune !
Don't get me wrong, but this wash sounds pretty confused,
and by the sound of it ; yo have perfectly good boards (20-30u")for solder
at hand .
May be wrong ; if that is so , keen to learn .
If you have gold on leads AS WELL ; than i would understood stripping
whatever yo can .
But it's a big if .
-----Original Message-----
From: Jonathan A Noquil [mailto:[log in to unmask]]
Sent: Wednesday, 15 March 2000 10:58
To: [log in to unmask]
Subject: Re: [TN] ??: [TN] Gold Removal
It is too dangerous to do this (using cyanide).
I think, it would be better to check if the higher thickness of gold
plating (on
fingers?) can have an insertion problem. Higher gold thickness does not
affect
reliability (solderability), it is good for customer but bad for the
supplier
due to price of gold.
If you are trying to remove 1 microns, you can not be sure that the etching
is
uniform throughout.
hope it helps
"Y.H. Woo" <[log in to unmask]> on 03/15/2000 07:28:41 AM
Please respond to "TechNet E-Mail Forum." <[log in to unmask]>; Please respond
to
[log in to unmask]
To: [log in to unmask]
cc: (bcc: Jonathan A Noquil/Cebu/Fairchild)
Subject: [TN]
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