Subject: | |
From: | |
Reply To: | |
Date: | Fri, 5 Nov 2004 16:54:23 -0600 |
Content-Type: | text/plain |
Parts/Attachments: |
|
|
Hello David,
The only difference between a MO and a MI classification is that MI's
are allowed to have halide activators. Both MO and MI fluxes must meet
the same requirements for SIR and corrosion testing, both cleaned and
uncleaned conditions. You are right in struggling to find a compelling
reason to back away from the MI flux types, especially if you have a
good reliability record using these products. Additionally, your
concern about solderability is a valid one, as it is well known that
halide activators can work better on some oxide layers.
Steve Stach
Austin American Technology
www.aat-corp.com <http://www.aat-corp.com>
-----Original Message-----
From: Dave Sorg
Sent: 11/4/2004 4:44 PM
To: [log in to unmask]
Subject: [TN] Guidelines for Cleaning by Flux Type
I'm trying to learn more about and evaluate the fluxes we use in our no-
clean hand soldering processes in a contract manufacturing environment.
In
the IPC-HDBK-001 "Handbook and Guide to Supplement J-STD-001", table
4-13B
includes "recommendations" for class 2 product that basically says to
use
only an L0, L1 or M0 rated flux for RO and RE type fluxes if the
residues
are to be left on the board. However, I'm told one of the tried and true
flux cores for 63/37 wire is the Kester #44, which has a ROM1 flux
designator. On top of that, I'm told that when supplemental flux is
needed,
an ROM1 liquid flux is often used, again without removing the residues.
Should we really be backing away from the ROM1 fluxes for no-clean/don't
clean hand soldering processes? I'm going to have a hard time selling
that
when the Kester #44 is a long time industry standard. Won't a lower
activity flux be problematic for the more difficult finshes like
palladium,
immersion tin and immersion silver?
Thanks for your comments
Dave Sorg
Manufacturing Engineer
Servatron
509-891-3137
[log in to unmask]
---------------------------------------------------
Technet Mail List provided as a 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/contentpage.asp?Pageid=4.3.16 for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100
ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a 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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------
|
|
|