Hi, Patrick,

In general I would say "No", it is not acceptable to remove unused pads on
internal layers, the reason being that these pads greatly assist in
"keying" the plated copper in the holes to the walls. For class 3 boards
undergoing thermal cycling, retaining unused pads therefore improves the
reliability of the PCB's.

Peter Duncan




                    Patrick Lam
                    <Patrick_Lam@S        To:     [log in to unmask]
                    ELINC.COM>            cc:     (bcc: DUNCAN Peter/Asst Prin Engr/ST
                    Sent by:              Aero/ST Group)
                    TechNet               Subject:     [TN] Remove unused "dead" pads on
                    <[log in to unmask]        internal layers
                    RG>


                    01/12/02 06:11
                    AM
                    Please respond
                    to "TechNet
                    E-Mail Forum."






Hi TechNetters,

For class 3 boards, is it acceptable to have unused pads removed on
interanal
layers.

Thanks,
Pat
This e-mail may contain SEL confidential information.  The opinions
expressed
are not necessarily those of SEL.  Any unauthorized disclosure,
distribution or
other use is prohibited.  If you received this e-mail in error, please
notify
the sender, permanently delete it, and destroy any printout.  Thank you.

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

Technet Mail List provided as a free service by IPC using LISTSERV 1.8d
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 delivery of Technet send e-mail to [log in to unmask]:
SET Technet NOMAIL
To recieve ONE mailing per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search previous postings at: www.ipc.org > On-Line Resources & Databases >
E-mail Archives
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for
additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700
ext.5315
---------------------------------------------------------------------------------





[This e-mail is confidential and may also be privileged. If you are not the
intended recipient, please delete it and notify us immediately; you should
not copy or use it for any purpose, nor disclose its contents to any other
person. Thank you.]

---------------------------------------------------------------------------------
Technet Mail List provided as a free service by IPC using LISTSERV 1.8d
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 delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL
To recieve ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
---------------------------------------------------------------------------------