Andre,
You give the answer to your problem. The board house screwed up. PCAD has
been around since 1986, and tens of thousands of boards have been designed
successfully.
This was an operator error. In it's default format, PCAD stores all aperture
settings in one file. The first part, which the CAM person used, is regular
274. The second, with which your files were generated with, is 274X. There
is a 3rd part as well, but I forget what it is. This file is not needed for
274X gerber files, but it is not uncommon for it to be included in a fab
package. The error occurred because the operator imported the 274 apertures,
apparently overwriting the embedded apertures. A simple glance at the data
should have told them it was in 274X format, and an external aperture list
was unnecessary.
The board house is responsible for delivering boards based on your data.
They did not. At the very least, I hope you did not have to pay for the
wrong boards.
In the future, I think if you remove the aperture file from the gerber data
set, it would remove the temptation for the board house to screw up. That
file is needed for the PCB program, however, so be sure to save it
somewhere.
David Ricketts
Pertek Engineering
Voice: 949-475-4485
Fax: 949-475-4493
----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of Andre Leclair
Sent: Tuesday, March 11, 2003 4:55 AM
To: [log in to unmask]
Subject: [TN] Aperture Data
Morning all
I have a question regarding Aperture List for Gerber Data. This is an area
I know little about so bare with me.
We had an incident with a PCB house which resulted in the boards being
manufactured with all traces/pads 0.020" bigger then they were supposed to
be. The shop said the problem arouse do to the way the aperture list was
set up.
The list has a set of 24 station #s with dimensions (which I understand get
translated to d-codes). These Station#s are then repeated further down
plus have extra #s to 999. We noticed that some of the dimensions in the
2nd set of station #s are differant from the 1st set. The 2nd set are the
correct #s.
The shop tells us their software (Infinite Graphics) will import the 1st
set then ignore the 2nd set of repeated #s then will continue to import any
station #s that are differant.
When we look at the Data with GC-Place and look at the used Apertures we
get the correct values.
Could the error be due to a differance in the way the software interprets
the list?..
The customer's data was created using P-Cad at least 10 years ago. The
format the Lists are in are the same for all the customers product. A
previous PCB shop had no reported difficulty.
Any ideas would be helpful
Thanks
Andre
---------------------------------------------------
Technet Mail List provided as a free service by IPC using LISTSERV 1.8e
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/html/forum.htm for additional
information, or 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 1.8e
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/html/forum.htm for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
-----------------------------------------------------
|
