Jim,
IPC-A-610 Rev D, Section 7.1.2.1 and 7.1.2.2 shows minimum bend radius
requirements which followed would not allow you to meet Class 3
requirements for what you are doing. No fracturing or cracking is
acceptable for Class 3 requirements.
As to long term reliability; it depends (cha-ching, another donation to
Doug's coffer). If the meniscus/seal is cracked there is potential of
ingression. Depending on construction and nature of the device there
could be shock transference damage to the internal interconnects. Since
the ability to test conclusively and assess long term reliability is
problematic and suspect at best, it is best to avoid the scenario
altogether.
Werner and others may have some additional advice for you.
Dewey

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of West, Jim
Sent: Wednesday, March 07, 2007 8:13 AM
To: [log in to unmask]
Subject: [TN] Lead coating meniscus cracking

Hi,
 
I'm looking for the IPC standard that defines allowable or not
allowable, meniscus cracking that extends down from the body to the
leads.  Can you have some cracking of the meniscus that covers the leads
of a component?  Is there a standard that I can reference?  Due to the
requirements of your application, we are forced to bend the leads of the
component next to where the meniscus stops which sometimes causes
cracking.
 
Thanks,
 


Jim West
Engineering Manager
Nexergy Inc.
www.nexergy.com
tel: (614) 351-6216
fax: (614) 324-1979



This email message and all attachments transmitted with it are intended
solely for the use of the addressee(s) and may contain legally
privileged, protected or confidential information. If you believe that
you have received this message in error, please notify the sender
immediately by email reply and please delete this message from your
computer and destroy any copies.

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

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