Our experiences are in line with this. OSPs applied with dip processes
have generally been better than those which were applied with conveyorized
processes. By "better" I mean "more consistent and less prone to having
unsolderable features".
Regards,
Greg Bartlett
Mercury Computer Systems
Chelmsford, MA
[log in to unmask]
----
Michael Barmuta wrote:
> Mr.Gross: I have to disagree with your statements regarding
"dip"
>processing of OSP's as "NOT good practice" compared to conveyorized
>processing. Control of OSP immersion processing is not harder than
>conveyorized. Chemical analysis and replenishment is basicaly the same.
>Immersion processing can be used with a timer/control system to obtain
>repeatable chemical exposure times. Since chemistry doesn"t know up from
down
>or left from right full immersion creates a uniform reaction across the
face
>and top and bottom of the panel. Issues such as clogged nozzles, uneven
spray
>patterns, top/bottom impingement, chemical carry over, areation of
chemistry
>etc. are eliminated {flood head technology can help).I believe the big
>advantage of conveyorized processing is it's ability to handle smaller
routed
>out parts.
> Both types of processing work well when setup and controlled
>properly. Please don't confuse immersion processing with low tech vs.
low
>complexity. Poor control and quality are more a function of lack of
>commitment than equipment :-).
> Regards
> Michael Barmuta
> Staff Engineer
> Fluke
Electronics
> Everett Wa.
> 425-356-6076
>On Sat, 9 Aug 1997 05:32:45 -0700 [log in to unmask] wrote:
>
>> From: [log in to unmask]> Date: Sat, 9 Aug 1997 05:32:45 -0700
>> Subject: Re: [TECHNET] FAB: OSP COATINGS
>> To: [log in to unmask]
>>
>> I agree with the cost issue..however, to apply an OSP with
>> "dip" tanks and the like is NOT good practice. It's too
>> hard to control the process. A conveyorized timed process
>> will gaurantee coverage, quality, etc. At one time, the
>> supplier of the materials would not sell to anyone who did
>> not have proper controls. I don't know what the situation is
>> today.
>
>
>RFC822 header
>-----------------------------------
>
>Return-Path: <[log in to unmask]>
>Received: from charon.mc.com by mc.com (SMI-8.6/SMI-SVR4)
> id OAA02597; Tue, 12 Aug 1997 14:29:37 -0400
>Received: from jefry.ipc.org (jefry.ipc.org [209.42.29.2])
> by charon.mc.com (8.8.4/8.8.4) with ESMTP
> id OAA04485 for <[log in to unmask]>; Tue, 12 Aug 1997 14:29:38
-0400
>(EDT)
>Received: from jefry (209.42.29.2) by jefry.ipc.org (LSMTP for Windows
NT
>v1.1a) with SMTP id <[log in to unmask]>; Tue, 12 Aug 1997
13:22:53
>-0500
>Received: from IPC.ORG by IPC.ORG (LISTSERV-TCP/IP release 1.8c) with
spool id
> 14019 for [log in to unmask]; Tue, 12 Aug 1997 13:22:52 -0500
>Received: from simon.ipc.org by jefry.ipc.org (LSMTP for Windows NT
v1.1a) with
> SMTP id <[log in to unmask]>; Tue, 12 Aug 1997 13:12:51
-0500
>Received: from fluke.com by simon.ipc.org via ESMTP
> (940816.SGI.8.6.9/940406.SGI) for <[log in to unmask]> id
NAA05374; Tue,
> 12 Aug 1997 13:19:44 -0700
>Received: by gateway.fluke.com id <35848-2>; Tue, 12 Aug 1997 11:12:13
-0700
>Priority: Normal
>MIME-Version: 1.0
>Content-Type: TEXT/PLAIN; CHARSET=US-ASCII
>Message-ID: <[log in to unmask]>
>Date: Tue, 12 Aug 1997 11:16:17 -0700
>Reply-To: [log in to unmask]
>Sender: TechNet Mail Forum<[log in to unmask]>
>From: Michael Barmuta <[log in to unmask]>
>Subject: Re: [TECHNET] FAB: OSP COATINGS
>X-To: [log in to unmask]
>To: [log in to unmask]
>X-UIDL: 260fb944a6b6ed1fbce53e83aa56d931
>
|
