TECHNET Archives

June 2000

TechNet@IPC.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
"Edward J. Valentine" <[log in to unmask]>
Reply To:
TechNet E-Mail Forum.
Date:
Tue, 20 Jun 2000 09:12:15 -0400
Content-Type:
text/plain
Parts/Attachments:
text/plain (75 lines)
Alexis - I'm not sure I understand the reason for the note you were asked to
add, since with reflow soldering you will get up to about 230 degrees C, and
with wave soldering you will hit about 260 degrees C. Anyways, as far as
substituting Dry Film for LPI, I honestly can't think of a single good
reason to do that. The cracking, in LPI is new to me, maybe it was one
"brand" of LPI that was improperly applied by the fabricator. I know when
LPI first came out, there were a number of problems with different
manufacturers, but I'm not aware of any current cracking problems. If you
get the information, please post it to TechNet so we can all understand the
situation. I would suggest in the interim, you try to get more detailed
information and justification before you switch because of the additional
difficulties you may have with dry film.

Ed Valentine
Electronics Manufacturing Solutions
8612 Mourning Dove Road, Raleigh, NC 27615
Phone: (919) 270-5145, Fax: (919) 847-9971
Email: [log in to unmask]
Website: http://www.ems-consulting.com

----- Original Message -----
From: Alexis Meehan <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, June 19, 2000 1:06 PM
Subject: [TN] PCB Materials/Soldermask


> For NEBS compliance, we have been advised by a consultant to add this
> note to our fab drawings:
> * Material must be thermal resistant to 150 degrees C.
> We have also been advised to switch from LPI soldermask to dry film to
> resist cracking which has been seen to happen after a few years.
> What are your experiences with these 2 issues? Do we really need to do
> this? I'm concerned about needlessly adding cost to our fabs. Any feedback
> would be appreciated.
>
> ********************
> Alexis Meehan
> [log in to unmask]
> LuxN, Inc.
> 570 Maude Court
> Sunnyvale, CA 94086
> "The Optical Renaissance Has Begun."
> http://www.LuxN.com
>
> ##############################################################
> 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
##############################################################

ATOM RSS1 RSS2