Mr. Holton,
Kudos! I couldn't add any more than what you said. I appreciate
designers design fancy products, but if their production dept
have difficulty building them, it is another story entirely.
I say the same thing for the discussion about reversed tantalum
capacitors. It is inevitable a human error creeps in regardless of
fancy assembly tricks mentioned in the discussion. I already
gone thru some of these tricks. They add extra assembly
overheads. As one mentioned, orienting all the caps in the
same direction is one practical solution fixing the problem at
the root. What I am saying is a lot of manufacturing defects (I
would say about 60% or more from my experience) are the
result of poorly designed products.
It is no good to do design reviews after designers finished
product layouts. It is seldom that design changes
recommended by a manufacturing engineer get implimented.
Many manufacturing defects get fixed or patched up on the floor.
This is especially true for sub-contract assembly houses.
It is very effective to do on-going design reivews when designers
start to layout boards and when component package selections
are made.
Sorry being too hard on designers, this is just my sound
opinion.
regards
Matthew Park
NII-Norsat International Inc.
>>> Ed Holton <[log in to unmask]> August 7, 1998
6:51 am >>>
As a manufacturing engineer, my advice is to visit your
manufacturing
engineering department and work with the M.E. They are
building your
designs, they know what they need. Get a tour of the production
line,
learn the basics of how the machines work, how the
components are placed,
how the machine handles them, keep out zones, how the
production line
works, etc. The M.E. dept should supply the capabilities of the
machines
so that your designs do not exceed machine capabilites. The
idea is that
the infamous wall between design and manufacturing no longer
exists. I
can't stress this enough, work with the manufacturing engineers
to make the
design something that can be easily built. Review component
placement,
component orientation, the mix of components used. The goal
is to develop
a design that can be built to a 6 sigma quality level, and this can
never
be done unless you work with the people building your design.
Ed Holton
Hella Electronics
[log in to unmask] on 08/06/98 06:11:51 PM
Please respond to [log in to unmask]; Please respond to
[log in to unmask]
To: [log in to unmask]
cc: (bcc: Ed Holton/Hella North America Inc.)
Subject: [TN] New Designer!!
Howdy,
I am relatively new to the designing of circuit boards so please
bear
with me and my petty questions. The company I work for has
been in the
business of designing its own circuit boards for several years
now. I
have found out that past designers had no formal training in the
processes of designing of the boards. What I am trying to say is
previous designers had vast knowledge in the way the designed
theoretically worked but, when it came to the layout of the board
and
where components were placed became a random process
throughout the
area of the board. There was some knowledge of where to put
certain
devices, but the designer seemed more interested in aesthetics
of the
board rather than proper function. What I am looking for is some
rules,
tips, and any information that will help me improve old and future
designs. Also, I have been given the task of converting old
designs
with regular components on them to an all surface mount
design. Again,
if anyone has any tips or past experience I would greatly
appreciate it.
THANKS FOR ALL THE HELP!!!
JASON MARKOSKY
[log in to unmask]
<mailto:[log in to unmask]>
################################################################
TechNet E-Mail Forum 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's web site (http://www.ipc.org) "On-Line
Services" section
for additional information. For technical support contact Hugo
Scaramuzza
at [log in to unmask] or 847-509-9700 ext.312
################################################################
################################################################
TechNet E-Mail Forum 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's web site (http://www.ipc.org) "On-Line
Services" section for additional information.
For technical support contact Hugo Scaramuzza at
[log in to unmask] or 847-509-9700 ext.312
################################################################
################################################################
TechNet E-Mail Forum 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's web site (http://www.ipc.org) "On-Line Services" section for additional information.
For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312
################################################################
|
