My experience mirrors Doug's. The stuff built up in the plumbing (closed loop system) like cholesterol in an artery. We had to re-plumb a portion of the machine. Guy Ramsey American Competitiveness Institute Senior Lab Technician / Instructor 610 362-1200 ext 107 -----Original Message----- From: TechNet [mailto:[log in to unmask]]On Behalf Of Douglas Pauls Sent: Friday, March 23, 2001 9:25 AM To: [log in to unmask] Subject: Re: [TN] Follow-up to solder flux problem After considerable thought, we have decided to go with the water soluble spacer idea. By the way, to answer some of your questions, the substrate we are using is a ceramic substrate, we are using a water soluble flux, and we use aqueous cleaning. *Paul, if you are going to use water soluble spacers, you will want to monitor your sump more often and step up your preventative maintenance. The dissolved spacer material tends to re-deposit where you least want them to, as well as building up on the walls of your cleaner, as well as the walls of your plumbing and pumps. It doesn't just "go away". Make sure the dissolved material does not come back to bite you. Doug Pauls Rockwell Collins ---------------------------------------------------------------------------- ----- 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 the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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 the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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 ---------------------------------------------------------------------------------