I agree with Matt, you need to determine if there is indeed separation
first and inspection without etching is a good way to do it.

Jim

-----Original Message-----
From: IPC-600-6012 [mailto:[log in to unmask]] On Behalf Of Byrne,
Matthew J (US SSA)
Sent: Tuesday, August 17, 2010 8:54 AM
To: [log in to unmask]
Subject: Re: [IPC-600-6012] opinion poll

The possibility of a separation at the knee between plating layers needs
to be evaluated without microetching the cross section mount.  If no
separation is found then no defect should be called out.  Microetching
helps in failure analysis.


Matt Byrne
Manufacturing Engineer, PWB Technology
BAE Systems, Room 795
600 Main St, Johnson City, NY 13790
607-770-2267
[log in to unmask]

-----Original Message-----
From: IPC-600-6012 [mailto:[log in to unmask]] On Behalf Of Brown,
Elaine
Sent: August 17, 2010 6:27 AM
To: [log in to unmask]
Subject: Re: [IPC-600-6012] opinion poll

It is non-conforming for both the crack and the plating separation.
The second picture is not so clear cut.  If indeed the area at the knee
is separation it is rejectable. 
If it is differential microetching, it is not.  Hard to tell from the
photo. 
I do not think we have any criteria for burning.    

Elaine

-----Original Message-----
From: IPC-600-6012 [mailto:[log in to unmask]] On Behalf Of Chris
Mahanna
Sent: Monday, August 16, 2010 1:19 PM
To: [log in to unmask]
Subject: EXTERNAL: [IPC-600-6012] opinion poll

Hi Everyone,

Attached is a picture of a thru-hole corner after thermal stress.  The
plating is pulse.  I believe the corner was 'burnt' because of the
geometry of the (conformant) negative etchback.  All the corners show
burn; some show blisters; only this one cracked.

In your opinion, what are the non-conformance(s) if any?


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]
______________________________________________________________________

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

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

NOTICE:  This email message is for the sole use of the intended recipient(s) and may contain confidential and privileged information.  Any unauthorized review, use, disclosure or distribution is prohibited.  If you are not the intended recipient, please contact the sender by reply email and destroy all copies of the original message.

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