Hi Mike
In Y14.5
Sec. 6.4.1 deals with straightness which references "bow"  (6.4.1.4).
Sec. 6.4.2 deals with flatness.
You are right they are different.
They can be additive.
Good Luck
Mike


                -----Original Message-----
                From:   Mcmaster, Michael
[mailto:[log in to unmask]]
                Sent:   Tuesday, June 13, 2000 1:03 AM
                To:     [log in to unmask]
                Subject:        [TN] Warpage, Flatness and Surface Profile

                I have a customer with a specification for bare board
warpage, but the part
                also has flatness and surface profile requirements on the
print.  The
                warpage requirement is in the customer's specification,
which also says that
                any print requirements supercede the spec.

                Are flatness and warpage the same thing?  Or are they
additive?  If the
                flatness spec is based on Maximum Material Condition do I
get to include the
                warpage as separate MMC condition that's in addition to the
flatness
                requirement?

                I've never been able to find anything in the ANSI Y14.5 for
warpage, bow or
                twist which are the terms most of us are familiar with.
Can anybody help
                me out here?
                Mike McMaster
                RF Product Engineer
                Merix Corporation
                Forest Grove OR
                503-992-4263


##############################################################
                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
##############################################################