There are manuf. Of ultrasonic cleaning equipment that use a sweeped freq.
which is supposed to eliminate the resonance problem. I would search the
archives.

-----Original Message-----
From: Blair K. Hogg [mailto:[log in to unmask]] 
Sent: Monday, 18 April 2005 9:39 AM
To: [log in to unmask]
Subject: Re: [TN] Ultrasonics

At a former employer we used resistor divider networks which had stamped
leads soldered to the component. The component was made from resistive ink
which was sliced in a serpentine pattern to create a high resistance. The
legs of the device had three prongs that would straddle the device in an
offset pattern. The manufacturer ultrasonically cleaned the parts after
soldering, which caused the stress areas in the stamped legs to develop
cracks and fail at a later date. Once the U/S cleaning was eliminated, the
problem disappeared.

Blair

>>> [log in to unmask] 04/18/05 09:15AM >>>
Technetters

I seem to remember somewhere that ultrasonics shouldn't be used to clean
populated PCB's. I have believed this to be due to damage inflicted to the
wire bonds within IC's and Xtals.

Is this the case can someone clarify what components (if any) cannot be
cleaned using ultrasonics?

Cheers

Mark


*******************************************************************
This email and any files transmitted with it are confidential and
intended solely for the use of the individual or entity to whom they
are addressed. If you have received this email in error please notify
the system manager.

This footnote also confirms that this email message has been swept
for the presence of computer viruses.

www.hubbell.com - Hubbell Incorporated

---------------------------------------------------
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
-----------------------------------------------------