Years ago, I had some interesting results on an SIR test with on OSP panels.
On one control panel, there was a corrosion pattern identical to a thumb
print in the copper. Obviously one person (I declined the step of
fingerprinting everyone, including myself) did not hold the panel by the
edges.
I passed the photographs around the plant and used it as a training aid for
proper board handling.
I also have seen fingerprints on VOC free flux spray patterns. This appears
as dewetted flux coverage where yield may be affected.
Aric Parr
Sr. Process Engineer
Eaton Corporation
1400 S. Livernois
PO Box 5020
Rochester Hills, MI 48308-5020
248 608 7780
[log in to unmask]
---------- Original Text ----------
From: C=US/A=INTERNET/DDA=ID/TechNet(a)IPC.ORG, on 9/7/99 6:04 PM:
Good practice Bruce ; as you said: than it works in store ;
and the result is very variable :
It is commonly known as "rust finger" nickname in toolmakers circles :
when you have a highly polished XYQZ supersteel moulding tool ;
some of the unfortunate fellows are literally banned from work on fishing
stages .
As the body acids do vary (you tell me, coke?, bad wine?, hormones?);
to see fingerprints developing on running tool is expensive business .
Gold I didn't see as critical as osp .
Our guys are trained : hold the edges only (anytime) .
They usually remember that only when I'm around .
PAUL
-----Original Message-----
From: Bruce Tostevin [mailto:[log in to unmask]]
Sent: Wednesday, 8 September 1999 6:06
To: [log in to unmask]
Subject: [TN] FW: Susceptibility of surface finishes to skin oils
> Is anyone aware of data or studies on whether or not, gold and OSP surface
> finishes are more susceptible to surface oils than HASL? We wear cotton
> gloves at incoming inspection, and on several smt lines, where we inspect
> and run non-HASL boards. There is a concern about fingerprint oils
> degrading the finish on an OSP board, which may sit several weeks in
> storage, and the concern with the immersion gold boards is that the thin
> finish is porous, and skin oils might cause nickel oxidation. Is anyone
> else doing this, or are we overly concerned about the vulnerability of
> these finishes to skin oils?
>
> Bruce Tostevin
> Benchmark Electronics
> Hudson, New Hampshire
>
##############################################################
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
##############################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following
text in
the body:
To subscribe: SUBSCRIBE TECHNET <your full name>
To unsubscribe: SIGNOFF TECHNET
##############################################################
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information.
If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or
847-509-9700 ext.5365
##############################################################
##############################################################
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
##############################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following
text in
the body:
To subscribe: SUBSCRIBE TECHNET <your full name>
To unsubscribe: SIGNOFF TECHNET
##############################################################
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information.
If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or
847-509-9700 ext.5365
##############################################################
##############################################################
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
##############################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in
the body:
To subscribe: SUBSCRIBE TECHNET <your full name>
To unsubscribe: SIGNOFF TECHNET
##############################################################
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information.
If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or
847-509-9700 ext.5365
##############################################################
|
