1). How about running some boards through the whole line without conformal
coating, then add the conformal coating.
2). In the past I have used the Kepner-Tregoe method of problem solving and
it starts with: when did the problem show up first, followed by: what
changed around that moment in time (list every and any change). And then
determine what impact any of those changes might have.
Good luck,
Ahne.
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Leland Woodall
Sent: Tuesday, 13 May, 2008 13:51
To: [log in to unmask]
Subject: Re: [TN] Stainless Steel Contamination Question
Richard,
We've found only one instance where this was found prior to the
conformal coating process.
That unfortunately opened up an entirely new area of search.
Thanks,
Leland
-----Original Message-----
From: Stadem, Richard D. [mailto:[log in to unmask]]
Sent: Tuesday, May 13, 2008 4:18 PM
To: TechNet E-Mail Forum; Leland Woodall
Subject: RE: [TN] Stainless Steel Contamination Question
Do you see it on the I.C.s prior to conformal coating? Or only after? I
am wondering if you have a source of metal strands within the coating
area, else in the conformal coat itself.
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Leland Woodall
Sent: Tuesday, May 13, 2008 3:00 PM
To: [log in to unmask]
Subject: Re: [TN] Stainless Steel Contamination Question
Paul,
I just asked this question to our process guys. They're not certain
about a couple of pieces of our equipment and are planning to provide me
with an answer tomorrow.
Is there some type of steel mesh filter on these things about which you
speak that will allow material to drop onto the product, rather than
being pulled through the system and deposited to an external location?
Leland
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Paul Edwards
Sent: Tuesday, May 13, 2008 3:20 PM
To: [log in to unmask]
Subject: Re: [TN] Stainless Steel Contamination Question
Leland,
Are your reflow and/or wave solder exhaust ducts attached a VOC thermal
reduction unit?
Paul
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Leland Woodall
Sent: Tuesday, May 13, 2008 12:06 PM
To: [log in to unmask]
Subject: Re: [TN] Stainless Steel Contamination Question
Thanks for your response, Reuven.
Here's the answers to your questions below...
1. Incoming material has been checked, all found to be OK
2. Boards barcoded and then re-bagged, stored, and subjected to
board cleaning machine prior to population
3. Metal brushes used at ICT much heavier material
4. No lead cutting process in facility
I appreciate your help in my search!
Leland
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Reuven Rokah
Sent: Tuesday, May 13, 2008 2:43 PM
To: [log in to unmask]
Subject: Re: [TN] Stainless Steel Contamination Question
1. Are the Ics before assembly have such wire?
2. Are the PCBs assemblies stored near air filters or un controlled
area?
3. May be metal hair brush is using for ICT contact cleaning etc.
4. May be through holes cutting leads process is used
Best Regards
Reuven ROKAH
e mail: [log in to unmask]
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Leland Woodall
Sent: Tuesday, May 13, 2008 9:28 PM
To: [log in to unmask]
Subject: Re: [TN] Stainless Steel Contamination Question
Jerry,
Our boards see no cleaning cycle. We have, though, looked at our
filters on our stencil and wave solder pallet cleaning machines, as well
as those at our conformal coating process.
No matches were found in any of the above. Either the material was
completely different, or else much larger in diameter than what we're
seeing.
Thanks again,
Leland
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Jerry Dengler
Sent: Tuesday, May 13, 2008 2:14 PM
To: [log in to unmask]
Subject: Re: [TN] Stainless Steel Contamination Question
Leland,
Do you wash these boards prior to finding the strand? If so does the
cleaner use a stainless steel wire mesh filter? Just another long shot.
Jerry
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of John Burke
Sent: Tuesday, May 13, 2008 1:58 PM
To: [log in to unmask]
Subject: Re: [TN] Stainless Steel Contamination Question
It is probably a magnetic grade of stainless if it is clinging to the
leads, can you confirm this?
John Burke
(408) 515 4992
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Leland Woodall
Sent: Tuesday, May 13, 2008 8:06 AM
To: [log in to unmask]
Subject: Re: [TN] Stainless Steel Contamination Question
David,
We haven't seen any of this interfering with or preventing a solder
joint from forming. In every instance, it's clinging to the leads.
Wouldn't that pretty much rule out our reflow ovens?
The earliest part of our process where this has been found is at
in-circuit test after the wave solder operation.
That leaves our Omron AOIs, our Huntron visioning stations, and our
flying probe machines. We've looked in and all around those processes,
and still are coming up with nothing.
Like trying to find a (stainless steel) needle in a haystack...
Leland
-----Original Message-----
From: David Greig [mailto:[log in to unmask]]
Sent: Tuesday, May 13, 2008 10:57 AM
To: Leland Woodall
Subject: RE: [TN] Stainless Steel Contamination Question
Are the fibres causing any problems with solder joint formation, if so
then trace backwards from the oven. If not then look around the oven and
forwards to the point at which they are observed.
What about the air/nitrogen source into the oven? Any bit of kit that is
opened and closed regularly.
The gaskets are used likely on electronic or even electrics enclosures,
particularly clam shell cases. The cut ends of the gaskets typically do
fray out loose fibres.
Best Regards
David Greig
-----Original Message-----
From: Leland Woodall [mailto:[log in to unmask]]
Sent: 13 May 2008 15:29
To: David Greig
Subject: RE: [TN] Stainless Steel Contamination Question
David,
Where in my manufacturing process might I find one of the knitted EMC
gaskets? Are you familiar with any particular machinery that would use
these?
Thanks again,
Leland
-----Original Message-----
From: David Greig [mailto:[log in to unmask]]
Sent: Tuesday, May 13, 2008 10:26 AM
To: 'TechNet E-Mail Forum'; Leland Woodall
Subject: RE: [TN] Stainless Steel Contamination Question
Perhaps an EMC gasket. One of the knitted mesh materials commonly used
consists of knitted stainless steel fabric. There may well be residues
of silicones and other lubricates used in the knitting or weaving.
Best Regards
David Greig
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Leland Woodall
Sent: 13 May 2008 14:47
To: [log in to unmask]
Subject: [TN] Stainless Steel Contamination Question
Importance: High
Hi Everyone,
We've had a problem lately with fine strands of stainless steel wire
being found on top of some of our .5 mm pitch ICs. This has caused both
internal and external issues, and we've yet to identify the source.
It's definitely formed wire, with a thickness ranging from 7 to 10
microns, and up to 3 mm in length.
Our automated optical inspection stations can only reliably detect
widths of 12 to 15 microns.
I've checked the internet in an attempt to find common applications of
this wire. I've found two, and they were for ultra-fine filters and
stencil screen mesh. We've investigated (I think) all of our machinery
that would utilize filters this small and have found no such usage.
I've also checked every stencil in our plant, and all of our mesh
material is some type of a plastic compound.
Do you have any idea where this stainless steel might be coming from?
Any suggestions would be sincerely appreciated!
Thanks,
Leland
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0 To
unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or
(re-start) delivery of Technet send e-mail to [log in to unmask]: SET
Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the
posts: send e-mail to
[log in to unmask]: SET Technet Digest Search the archives of previous
posts at: http://listserv.ipc.org/archives Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100
ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0 To
unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or
(re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing
per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16
for additional information, or contact Keach Sasamori at [log in to unmask]
or 847-615-7100 ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0 To
unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or
(re-start) delivery of Technet send e-mail to [log in to unmask]: SET
Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the
posts: send e-mail to [log in to unmask]: SET Technet Digest Search the
archives of previous posts at: http://listserv.ipc.org/archives Please
visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for
additional information, or contact Keach Sasamori at [log in to unmask] or
847-615-7100 ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0 To
unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or
(re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing
per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives
Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100
ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0 To
unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or
(re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing
per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives
Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100
ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0 To
unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or
(re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing
per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives
Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100
ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0 To
unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or
(re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing
per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives
Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100
ext.2815
-----------------------------------------------------
=======================================================================
======
This email and any attachments thereto may contain private,
confidential, and privileged material for the sole use of the intended
recipient. Any review, copying, or distribution of this email (or any
attachments thereto) by others is strictly prohibited.
If you are not the intended recipient, please contact
[log in to unmask]
immediately and permanently delete the original and any copies of this
email and any attachments thereto.
=======================================================================
======
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0 To
unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or
(re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing
per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives
Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100
ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0 To
unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or
(re-start) delivery of Technet send e-mail to [log in to unmask]: SET
Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the
posts: send e-mail to [log in to unmask]: SET Technet Digest Search the
archives of previous posts at: http://listserv.ipc.org/archives Please
visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for
additional information, or contact Keach Sasamori at [log in to unmask] or
847-615-7100 ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16
for additional information, or contact Keach Sasamori at [log in to unmask] or
847-615-7100 ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------
|
