We have recently had some cleanliness testing issues.
We are washing SMT CCA's with RMA solderpaste in a batch washer (AQ400RU)
with Armakleen E2001A saponifier. The CCA's are being cleanliness Tested
with an Omega Meter Model 600 SMD without heat.

Cards that easily pass cleanliness testing at the 14uGNaCl/in squared
acceptance level refered to in MIL-P-28809 have visible traces (under
magnification) of whitish flux residue under and around many of the SMT
components.

I do understand that the cleanliness tester is not meant to be an
analytical tool, but is a tool to be used for process control.

Here are my questions.
What do others in the industry do to decide when CCA's are clean enough?
Do you come up with your own acceptable cleanliness test level using SPC
techniques?
Any other comments?

Many thanks in advance
Virgil



Virgil Lenton - Manufacturing Engineering
SED Systems - A Division of Calian
Saskatoon, Saskatchewan
Canada

---------------------------------------------------
Technet Mail List provided as a free 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/html/forum.htm for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
-----------------------------------------------------