Brad,
Having not seen your situation The following has worked successfully with
connectors on the backside of a double-sided surface mount assembly without
adhesive. Have you tried selective wavesolder fixtures? You can use the
selective wave fixtures (G10 or G11) whether you solder on the frontside or
backside of the surface mount assembly. Selective wave has openings for the
wave solderable components only and has pockets for chips and such keeping
the solder joint below eutectic.
A word of caution if you do glue-reflow-and-wave. For ceramic capacitors
thermocouple a few to assure the wave process does not thermally shock the
chips between the pre-heat and wave.
We have been successfully g-r-w assemblies for greater than 10 years.
B
-----Original Message-----
From: Vanderhoof, Brad [mailto:[log in to unmask]]
Sent: Friday, March 16, 2001 9:46 AM
To: [log in to unmask]
Subject: Re: [TN]
There are many potential problems with this type of process including
material incompatability, solder balls in the adhesive, adhesive
contamination of the pads, etc.
Having given this warning I will say I have been extremely successful with
this approach. The resulting solder joints look fine (visually, cross
section, test, field experience -- IPC class 2,3)
Best of Luck
Brad Vanderhoof
-----Original Message-----
From: Steffen, Don E [mailto:[log in to unmask]]
Sent: Friday, March 16, 2001 7:27 AM
To: [log in to unmask]
Subject: [TN]
TECHNETTERS
I am currently trying to set up an experiment using paste printing and glue
dot dispensing to help reduce solder wave defects, I feel I have covered all
of my bases as far as stencil design, adhesive dot parameters and reflow
profile, however my problem is that I am facing a certain amount of
skepticism about creating unreliable solder joints by reflowing then wave
soldering the joints. I was wondering if anyone out there has went through
this change and has some feedback that could help me put these fears to
rest. This is a no-clean solder process.
Donn E Steffen
Senior Quality Engineev
VDO Control Systems
Ph# 219-920-6052
Fax# 219-925-8710
Cell# 219-417-2926
Pager# 219-430-2826
-----------------------------------------------------------
This Mail has been checked for Viruses
Attention: Encrypted Mails can NOT be checked !
***
Diese Mail wurde auf Viren ueberprueft
Hinweis: Verschluesselte Mails koennen NICHT geprueft werden!
------------------------------------------------------------
----------------------------------------------------------------------------
-----
Technet Mail List provided as a free service by IPC using LISTSERV 1.8d
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 delivery of Technet send the following message: SET
Technet NOMAIL
Search previous postings at: www.ipc.org > On-Line Resources & Databases >
E-mail 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 1.8d
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 delivery of Technet send the following message: SET Technet NOMAIL
Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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
---------------------------------------------------------------------------------
|
