I haven't seen any industry guidelines, however, occasionally a customer who
has been "burned" will specify .002 max.  This is achievable with straight
masking operations.  If performing separate "postplugging" operations after
primary mask application and surface finishing etc., it's important to
insure that the primary mask has a clearance at the location that is to be
postplugged.  Otherwise if the hole is partially plugged etc., the secondary
masking operation will leave a very undesirable bump approx. .005-.006 high.
These specialized operations drive inspectors and CAM operators absolutely
crazy. Additionally, most customers are neither consistent with their data
or assembly needs.  Typically, the masking information is the least
considered by a designer.  Couple this with third party contract assemblers
and you have numerous opportunities for error.

Mike Bailey
Director of Engineering
McCurdy Circuits Inc.
4900 E. Hunter Ave.
Anaheim, CA  92870
Phone: 714 507-4900 Ext 253
FAX: 714 507-4911
e-mail: [log in to unmask] <mailto:[log in to unmask]>

-----Original Message-----
From: Rick Babyak [mailto:[log in to unmask]]
Sent: Friday, March 31, 2000 4:47 AM
To: [log in to unmask]
Subject: [TN] via plugging


Is there any acceptance criteria or a spec out there that covers via
plugging with mask/ink?



Rick Babyak
Process Engineer
Proto Circuit Inc.
7 Ascot Parkway
Cuyahoga Falls, OH 44223
330-572-3401  Fax:330-572-3434
[log in to unmask]

##############################################################
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
##############################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following
text in
the body:
To subscribe:   SUBSCRIBE TECHNET <your full name>
To unsubscribe:   SIGNOFF TECHNET
##############################################################
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information.
If you need assistance - contact Keach Sasamori at [log in to unmask] or
847-509-9700 ext.5315
##############################################################

##############################################################
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
##############################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in
the body:
To subscribe:   SUBSCRIBE TECHNET <your full name>
To unsubscribe:   SIGNOFF TECHNET
##############################################################
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information.
If you need assistance - contact Keach Sasamori at [log in to unmask] or
847-509-9700 ext.5315
##############################################################