I know our stencil manufacturer is very knowledgeable.  You may want to ask
yours if they have good knowledgeable staff able to help.  Ours is IRI
alphametals located in Binghamton, NY and has a guy named "Ron" who helped
us immensely.  He was very helpful and gave us rules of thumb we work to.
You should probably also have IPC 7525 (I think) that is about stencil
designing.  Lenny ERG.   www.ergpower.com

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Dave Connitt
Sent: Wednesday, January 07, 2009 6:59 AM
To: [log in to unmask]
Subject: [TN] Solder Paste Stencil Guidelines

Hello,
Does anyone know of a current standard for the generation of solder paste
stencil apertures? I know the general rule is 10% less than the copper pad.
We use PCB Libraries design guides here for all our symbol generation but I
don't think it supports "window paning" or "home plate"
type apertures. We currently have been leaving the special aperture
generation up to our stencil vendor and review the results prior to release
for manufacture.  There has been some talk here about incorporating those
apertures in the actual PADS PCB file which is why I am asking about
standards.
 
Thanks,
 
Dave Connitt CID+
Printed Circuit Designer
L3 Fuzing & Ordnance Systems
A Wholly Owned Subsidiary of:
L3 Communications
3975 McMann Road
Cincinnati, Ohio 45245
Ph. 513- 943-2010   Fax 513-943-2288

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