Hi Ken/Rich,
I'm not as comfortable with coat over no-clean with a hand solder
operation as with a typical reflow process since the flux residues tend
to flow away from the connection as it is heated, and often do not reach
an adequate reflow temperature to volatize active elements. Certainly
you can test to see what the residues are but ionic conductivity is
ineffective. Recommend IC testing to determine what you have. Also all
no cleans are not created equal so the test is a good idea to see what
you have in any case. 

Mel

Mel Parrish
FSO/Director Training Materials Resources
STI Electronics Inc.
261 Palmer Road
Madison, AL 35758
256 705 5530
[log in to unmask]
www.stielectronicsinc.com

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Richard Kraszewski
Sent: Friday, March 05, 2010 12:15 PM
To: [log in to unmask]
Subject: Re: [TN] Conformal Coat Over No-Clean Flux

In a previous life with a contract manufacturer that did a class 3
automotive, we routinely coated over no clean residues with few or any
issues.  I never felt comfortable with that however and am very glad to
be cleaning our no-clean presently.  You do wind up getting areas that
are quasi- coated with a CC & Flux -residue blend of some type.  I
suspect that perhaps that SR coatings may be more forgiving along this
line.  If I were a coating manufacturer however, I would contest any
claim of defective coating with the fact that you don't have "our CC" in
that failed spot(S). 

Rich Kraszewski

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Ken Bloomquist
Sent: Thursday, March 04, 2010 11:20 AM
To: [log in to unmask]
Subject: [TN] Conformal Coat Over No-Clean Flux

We have a twelve leaded, through-hole component that has to be hand
soldered
on the circuit board. The assembly gets conformal coated with urethane.
We
would like to hand solder these twelve leads using no-clean and then
conformal coat the board. The component would be added as a final step
after
the assembly has first been cleaned.

Since this is not a "total no-clean" process do you see any issues
applying
conformal coat over these twelve no-clean solder joints?

Best regards,

KennyB


______________________________________________________________________
This email has been scanned by the MessageLabs Email Security System.
For more information please contact helpdesk at x2960 or
[log in to unmask] 
______________________________________________________________________

---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
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
-----------------------------------------------------

______________________________________________________________________
This email has been scanned by the MessageLabs Email Security System.
For more information please contact helpdesk at x2960 or
[log in to unmask] 
______________________________________________________________________

---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
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
-----------------------------------------------------

______________________________________________________________________
This email has been scanned by the MessageLabs Email Security System.
For more information please contact helpdesk at x2960 or [log in to unmask] 
______________________________________________________________________

---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
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
-----------------------------------------------------