Ken Patel asks: I have been given a task of implementing Leadfree change over. We are OEM and our CM to build assemblies for us. Part of my responsibility is to come out with a clear plan for transition from Pb containing to leadfree assemblies. Does anyone has created such plan and willing to share with me. This plan of attack will help us in moving smoothly to leadfree with fewer headaches. I know I have to work with not only CM but also with suppliers. Ken, I have been meaning to answer this one for a while. I don't think you can have a generic plan for transitioning to lead-free, any more than you can for any other manufacturing process, because it all depends on your materials of construction and your chosen process parameters, for your product. I will have a different approach than you than would our Star Trek obsessed friend, Dewey. In essence, you are crafting a new manufacturing process from the ground up. You must understand the impact of reflowing solder at 30-40C higher temperature on your materials of construction. Much will depend on what your equipment can or cannot do, so you have to answer the question not only for your manufacturing processes, but your CMs as well. That being understood, here is a general approach to consider. Will your components handle the hotter temperature without loss of life Is your equipment capable of providing the 30-40C hotter temperatures What is the effect of the hotter temperatures on laminate? Do you need to go to a higher Tg laminate? What is the effect on solder mask? will it degrade at the hotter temperatures? Will it withstand fewer reflow cycles, i.e. rework? What are the effects of the flux? Is is cleanable? If so, with what materials and processes? If not, will it support dendritic growth What is the effect of the hotter temperatures on via or PTH reliability? What is the fatigue life of the new solder joints? What is the life in thermal cycle. Yes, it is a LOT of work since you cannot assume that all the reliability or quality metrics or guidelines we have used for years are still applicable. The best thing that you can do to help develop a test plan for transition is to participate in the IPC. The A-610 and J-STD-001 groups meet in Huntsville, Alabama in August. It would give you access to all the right people and most are pretty helpful. Technet also has many qualified consultants or technical experts which can contact you off-line to assist you in the development of your plan. Doug Pauls --------------------------------------------------- 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 847-509-9700 ext.5315 -----------------------------------------------------