TECHNET Archives

October 2010

TechNet@IPC.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
Reply To:
Date:
Mon, 11 Oct 2010 23:52:00 +0200
Content-Type:
text/plain
Parts/Attachments:
text/plain (203 lines)
Poor wedding, with other words. How do you perform the die'n'pray ?  It's a 
little unsafe method, you easily introduce false evidence. I use to cool 
down to LN2 first and knock the part against a granite stone or anything 
else that is steady. If the wetting is rotten, you get a 'ping' and off 
jumps the BGA. If you don't get that result, the main part of solder joints 
are very, very good. Now, still at LN2 level, bend the board over a pencil 
(if the boards longitude is > 10"  and a prop smaller object if < etc). I 
don't have the recommended radius in my head. If the BGA is still there, I 
bet all sjs are good. Not a test for rookers, but with years of component 
testing behind, you get an idea wheather the sjs are catastrophic or not. I

If you could blow up  the pics two or three times, it would be a better 
situation  for us old dogs. I have seen what you see with your younger eyes, 
will look in my piles for some reports.  But Dave the hawkeyed or Wayne the 
wizard will probably have an answer befor that.

Inge

----- Original Message ----- 
From: "Thayer, Wayne - IIW" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, October 11, 2010 8:54 PM
Subject: Re: [TN] Mech. damage or poor wetting?


Never mind.  I just read the original post.  I'm betting the whole shebang 
is due to poor wetting--that's why the correlation to the fanout escape.

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Thayer, Wayne - IIW
Sent: Monday, October 11, 2010 2:52 PM
To: [log in to unmask]
Subject: Re: [TN] Mech. damage or poor wetting?

What's going on with the picture of the cross section?  The ball isn't 
wetting down the side of the plated pad.

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Chris Mahanna
Sent: Monday, October 11, 2010 2:41 PM
To: [log in to unmask]
Subject: Re: [TN] Mech. damage or poor wetting?

Here are a few pictures
http://ipc-technet.groupsite.com/gallery/16011

this job is a mixed bag.  Currently we suspect soldering, cratering, ICT and 
t-cycling damage

Chris

From: [log in to unmask] [mailto:[log in to unmask]]
Sent: Monday, October 11, 2010 2:22 PM
To: TechNet E-Mail Forum; Chris Mahanna
Cc: [log in to unmask]
Subject: Re: [TN] Mech. damage or poor wetting?


Hi Chris - do you have any pictures you can share?

Dave Hillman
Rockwell Collins
[log in to unmask]

Chris Mahanna <[log in to unmask]>
Sent by: TechNet <[log in to unmask]>

10/11/2010 11:29 AM
Please respond to
TechNet E-Mail Forum <[log in to unmask]>; Please respond to
Chris Mahanna <[log in to unmask]>


To

[log in to unmask]

cc

Subject

[TN] Mech. damage or poor wetting?







We have a BGA dye-n-pry job that shows board side sj damage with a strong 
correlation to fan-out clocking.
We also have some microsection evidence of poor wetting.
All damage/dye is on perimeters.

Is this an indication of heat sinking and subpar wetting, or can it be 
completely mechanical?  Both?

Thanks

Chris

______________________________________________________________________
This email has been scanned by the MessageLabs Email Security System.
For more information please contact helpdesk at x2960 or [log in to unmask]
______________________________________________________________________

---------------------------------------------------
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 has been scanned by the MessageLabs Email Security System.
For more information please contact helpdesk at x2960 or [log in to unmask]
______________________________________________________________________

---------------------------------------------------
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 e-mail and any files transmitted with it may be proprietary and are 
intended solely for the use of the individual or entity to whom they are 
addressed. If you have received this e-mail in error please notify the 
sender.
Please note that any views or opinions presented in this e-mail are solely 
those of the author and do not necessarily represent those of ITT 
Corporation. The recipient should check this e-mail and any attachments for 
the presence of viruses. ITT accepts no liability for any damage caused by 
any virus transmitted by this e-mail.

______________________________________________________________________
This email has been scanned by the MessageLabs Email Security System.
For more information please contact helpdesk at x2960 or [log in to unmask]
______________________________________________________________________

---------------------------------------------------
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 has been scanned by the MessageLabs Email Security System.
For more information please contact helpdesk at x2960 or [log in to unmask]
______________________________________________________________________

---------------------------------------------------
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 has been scanned by the MessageLabs Email Security System.
For more information please contact helpdesk at x2960 or [log in to unmask] 
______________________________________________________________________

---------------------------------------------------
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
-----------------------------------------------------

ATOM RSS1 RSS2