Michael, Gaby's methods pretty much reflect our incoming procedures. We have certified suppliers, based on quality and delivery, that get the skip lot treatment. I would just want to comment that the laws of probability do not seem to apply in skip lot programs. All problems occur on skipped lots and never on inspected lots - forgive the slight over-statement. ;^) Gary Camac Gabriela Bogdan wrote: > Michael, > Your problem is very real, we perform incoming inspection for printed circuits. > I will not go into many details, but : > Visual inspection is done for each lot on a sample basis, as well as dimensional > testing. > Cross sections for copper thickness in holes and solderability are done following a > skip lot program based on supplier, number of layers, PCB, and supplier history. > We try to order only from suppliers with good history, thus we can widen the intervals > between tests. > New suppliers are tested for each lot for a while, and if successful, they enter the > skip lot. > We are a CM , and do the purchasing too, being totally responsible for the assemblies. > Gaby > > Michael Blackburn wrote: > > > The company I work for is in the process of moving from inspecting incoming > > pcbs to a "dock to stock" program. Also, we are outsourcing more of our pcb > > assemblies and the feeling is that the CM should be responsible for the > > quality and reliability of the bare board. > > > > Does anyone have feedback about dock to stock programs? What kind of SPC are > > you doing? Is a thourough audit of the board vendor and CM enough? What kind > > of scrap/defect rates are you seeing? > > > > The reason I'm asking about this is because in a recent post about baking > > boards, someone responded that they were doing copper plating thickness > > measurement in the wall of the PTH. We experienced the same problem (blow > > holes) and ended up doing the same test. > > > > I would appreciate any feedback/experiences you might have. > > > > Sincerely, > > > > Mike Blackburn > > > > ############################################################## > > TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c > > ############################################################## > > To subscribe/unsubscribe, send a message to [log in to unmask] with following text in > > the body: > > To subscribe: SUBSCRIBE TECHNET <your full name> > > To unsubscribe: SIGNOFF TECHNET > > ############################################################## > > Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional > > information. > > If you need assistance - 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 1.8c > ############################################################## > To subscribe/unsubscribe, send a message to [log in to unmask] with following text in > the body: > To subscribe: SUBSCRIBE TECHNET <your full name> > To unsubscribe: SIGNOFF TECHNET > ############################################################## > Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional > information. > If you need assistance - contact Keach Sasamori at [log in to unmask] or > 847-509-9700 ext.5315 > ##############################################################