Hi Ken - I suggest taking apart one of the capacitors in the "as received" condition and in the "as wave soldered" condition - if there is metallization missing then you would have proof that the cleaning process is not the root cause. Dave Hillman Rockwell Collins [log in to unmask] "Bloomquist, Ken" <[log in to unmask]> Sent by: TechNet <[log in to unmask]> 04/27/2007 10:28 AM Please respond to TechNet E-Mail Forum <[log in to unmask]>; Please respond to "Bloomquist, Ken" <[log in to unmask]> To [log in to unmask] cc Subject Re: [TN] Metalized Poly Caps Thanks Steve for putting up the pictures, now here's the situation. We are having a higher than expected failure rate on these capacitors. They are supposed to be .22 mfd and are testing at around .12 mfd after assembly. The manufacturer is saying that it is because we are getting water inside of them during the cleaning process. A possible cause is that we are breaking the "seal" on the end or possibly putting them into the cleaning process while they are still hot from the wave solder. We've built assemblies using these types of parts for decades and haven't seen this sort of problem in the past. We pulled a couple of these caps apart and that is what the photos are showing. It appears that the metallization is missing on part of the film. They say that this is due to the wash process. The wash is an inline wash system using DI water, no saponifier. The contractor got a new wash system a few months ago but it's a typical inline wash using the same temps and speeds that they used on the old system. Have any of you been seeing problems with these caps lately or have any insight into this problem? See the photos below. http://stevezeva.homestead.com/files/cap1.jpg http://stevezeva.homestead.com/files/cap2.jpg Thanks, KennyB --------------------------------------------------- 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 ----------------------------------------------------- --------------------------------------------------- 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 -----------------------------------------------------