Richard, your question seems to be posted for IPC specifically but was placed on TechNet. J-STD-020C Clause 4 has a note under Tables 4-1 (SnPb Process) and 4-2 (Pb-free Process) that states: Note 4: Components intended for use in a ''lead-free'' assembly process shall be evaluated using the ''lead free'' classification temperatures and profiles defined in Tables 4-1, 4.2 and 5-2 whether or not lead free. Component classification should be established by the manufacturer towards the most demanding assembly process. Companies reclassify components when those components are manufactured with characteristics that enable use in LF mfg. I'll share your recommendation to have multiple classification levels with the committee. However, industry is having a hard time correlating part numbers to lead finishes and I'm not sure there will be buy-in for multiple process temperature classes as well. Jack Jack Crawford, IOM IPC Director Certification and Assembly Technology [log in to unmask] 847-597-2893 FAX 847-615-5693 3000 Lakeside Drive, Suite 309 S Bannockburn, IL, 60015 -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Stadem, Richard Sent: Monday, July 25, 2005 8:29 AM To: [log in to unmask] Subject: [TN] Jack, I have had experiences lately with components that were formerly a class 3 MSD level coming in now classified as a class 5 or 5A, because the termination finish was changed to a lead-free finish. Apparently the component vendors feel that if they provide a lead-free finish, they are implying the component can undergo a lead-free process with a higher reflow temperature. To ensure the components survive the higher reflow temperatures seen in the lead-free process, they call out a higher MSD level, typically upgrading by a factor of two. This means that we will receive the same part with different MSD levels. This causes us to handle components as if they are a level 5A when they are actually a level 3, even though we are using only the leaded process and reflowing at the lower solder temperatures. As seen by the rash of emails back and forth in the Technet Forum, apparently I am not the only one with this problem. Many of us are not required to change over to the lead-free solders (heavy industrial equipment, military suppliers, etc.). The "fix" for this problem seems to be very simple. I am wondering if the J-STD-020 cannot be changed to call out two different MSD levels, one for use on tin/lead processes, and one for use on lead-free processes. We know that the change in the part number to signify a lead-free finish controls whether the part is lead-free. However, the package does not change. So we should be unaffected if our purchase order calls out the non-leadfree component part number, right? Well, the problem is that most component vendors discontinue the lead-bearing finish as soon as the lead-free finish is available. This leaves us no choice except to purchase the lead-free part and handle it at the higher MSD level. But the part itself has not changed. So why should we have to handle it differently if neither the part nor our process have not changed? Most disturbing, why did the part vendors not discuss this with IPC? We have seen no communications from anyone on how this was being handled. It would have been much easier to come up with a two-number rating system that indicated the handling requirements based on the intended process. If not, then some type of historical preservation system should be put in place for those who will not change to a lead-free process, so that we do not place unnecessary limitations on floor life and bake out times without reason to do so. To further complicate the problem, many component vendors did not even change their part numbers when they changed over to a lead-free finish. I actually have several parts that come in both tin/lead and tin-only with the same exact part number. I have no way of knowing which lots are which. The part number never changed. Some type of controls have to be placed over this situation. Historically the industry depended on the IPC to provide this. The problem is not a minor one, it has severe impact on material handling cost for thousands of different OEMs and CEMs worldwide. This is a major problem. Can you tell us what the IPC is doing to address this? --------------------------------------------------- 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 ----------------------------------------------------- --------------------------------------------------- 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 -----------------------------------------------------