While inspecting a board produced by mass manufacturing techniques, I noticed the backside had been selectively soldered. The areas where through hole components are located appear to have been gasketed off (as detected by observing the no-clean flux residue) by either the fluxing or wave-like processing. Any ideas as to how that was done? Its clear that the board wasn't wave soldered as there are open PTH's in the areas not soldered. A multi-nozzle solder fountain? --------------------------------------------------- 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 -----------------------------------------------------