Cal,

Everyone has brought up great concerns about the effect of the
ultrasonics on the components, but I would also be concerned with the
no-clean residues.

You mention that a general cleaning product was being used.  As far as I
know, all of our customers cleaning no-clean flux from boards are using
a chemistry designed specifically to remove flux residues, not a
degreaser.  No-clean residues are typically the toughest to remove and
the chemistry chosen plays a large role in the process.  I would
definitely have samples tested for residues.

If there are residues present anywhere there could be a real cause for
concern.  Partially cleaning certain no-clean formulations and not
removing all of it, can really cause some problems.  You should be
especially be concerned with residue left under the BGAs.

Steve Pence

Unit Design, Inc.
576 Explorer Street
Brea, CA 92821
714-672-9944
www.unitdesign.com


Cal Driscoll wrote:

>Hello All-
>Recently I was away on Holiday and when I came back....there was a Branson
>Utlrasonics system being used to clean our newly assembled PCB's. The
>machine is a standard ultrasonics (parts cleaner I call it) bath using a
>general cleaner/degreaser.
>
>Facts:
>Our process is:
>- No clean
>- double sided
>- mix technology
>- Discrete (tants, Chips resistors)
>- BGA's
>- QFPs
>- PLCC's
>- ASICS
>- Connectors
>- Headers
>- Electrolytic Caps
>
>Concerns:
>- Ultrsonics damaging internals on IC's
>- Residues left after cleaning
>- Effects on Programmable IC's
>- .....Just General over all reliability.
>
>
>I have huge concerns on the over all cleanliness and reliability. Any info
>supporting or declining this is of interest.
>
>Thanks in advance,
>
>Cal
>
>Caldon Driscoll
>Program Manager, Circuit Board Manufacturing
>CTDI
>1373 Enterprise Drive
>West Chester, PA 19380
>610-793-8098
>WWW.CTDI.COM
>
>---------------------------------------------------
>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 847-509-9700 ext.5315
>-----------------------------------------------------
>
>
>

---------------------------------------------------
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 847-509-9700 ext.5315
-----------------------------------------------------