David, I would also like to get a copy of your paper since we have experience issues associated with contamination on mil spec CCA's Thanks, Jack Lusby Northrop/Grumman ESSS [log in to unmask] direct (410)552-2886 fax (410)981-5361 > -----Original Message----- > From: Debbie Kenney [SMTP:[log in to unmask]] > Sent: Monday, June 24, 2002 2:16 PM > To: [log in to unmask] > Subject: Re: [TN] Cleaning of Military PWAs That Have Been Soldered > withNo -CleanFlux > > I would also like to get a copy. > > Debbie Kenney > Engineer > M-Flex / AMT > Direct (714) 688-5242 > Fax (714) 996-3834 > [log in to unmask] > > > -----Original Message----- > > From: Gordon F. Davis Jr [SMTP:[log in to unmask]] > > Sent: Friday, June 21, 2002 4:30 AM > > To: [log in to unmask] > > Subject: Re: [TN] Cleaning of Military PWAs That Have Been Soldered > > withNo-CleanFlux > > > > May I get an e-copy of the paper you refered to as well. I also work > for > > a > > military supplier, but we clean everything. I would like to get further > > info on no-clean. > > > > Gordon Davis > > Application Engineer > > Rockwell Collins > > > > > > > > > > David Douthit <[log in to unmask]>@ipc.org> on 06/20/2002 09:10:13 PM > > > > Please respond to "TechNet E-Mail Forum." <[log in to unmask]>; Please > > respond > > to David Douthit <[log in to unmask]> > > > > Sent by: TechNet <[log in to unmask]> > > > > > > To: [log in to unmask] > > cc: > > > > Subject: Re: [TN] Cleaning of Military PWAs That Have Been Soldered > > withNo-CleanFlux > > > > > > You have landed in a very nasty area. You are correct to be concerned > > about > > contamination issues. > > Even if the residues from the flux do not create migration/leakage > current > > problems they may > > collect other airborne contaminates that can cause problems. > > > > Process, shipping, and storage control are critical to the reliability > of > > the circuitry. > > > > If you wish I have a paper I presented in May of 2001 titled > > "Avionics Systems, Reliability, and Harsh Environments" > > that I could e-mail you. The information in the paper will > > give you a good idea of what type of airborne contamination > > issues you may have to deal with. > > > > David A. Douthit > > Manager > > LoCan LLC > > > > Bogert wrote: 6/20/2002 Folks is anyone manufacturing military PWAs > using > > no-clean flux and not cleaning the PWAs prior to shipment? If so, what > is > > your reliability experience with this process? We are considering a > > military application (Class 2) where mixed technology (SMT and PTH) PWAs > > will be soldered using no-clean flux and then not conformal coated > > (assuming the uncoated PWAs can pass our temperature/humidity > > qualification > > testing). Although the no-clean flux we will use should be benign (we > are > > having SIR testing performed to confirm this and Omegameter testing), I > am > > concerned that contamination may be introduced by other shop processes > > such > > as mechanical assembly, testing, etc., even if one uses gloves or > fingere > > cots during handling. One could argue that after shipment, since the > PWAs > > are not conformal coated, you can introduce contamination in the field > and > > therefore, why not not clean prior to shipment. We may be performing > board > > testing (boundry scan, bed-of-nails, etc) on PWAs that have been > soldered > > using no-clean flux. I understand that certain noclean flux can impede > > this testing, and also, may cause problems in event we need to conformal > > coat the PWAs. Any comments on this subject will be appreciated. > > > > > > > > > -------------------------------------------------------------------------- > > ------- > > Technet Mail List provided as a free service by IPC using LISTSERV 1.8d > > 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 delivery of Technet send e-mail to [log in to unmask]: > > SET Technet NOMAIL > > 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 > > > -------------------------------------------------------------------------- > > ------- > > -------------------------------------------------------------------------- > ------- > Technet Mail List provided as a free service by IPC using LISTSERV 1.8d > 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 delivery of Technet send e-mail to [log in to unmask]: > SET Technet NOMAIL > 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 > -------------------------------------------------------------------------- > ------- --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d 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 delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL 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 ---------------------------------------------------------------------------------