Howard, I agree 100% with Andre regarding reel sizes for highly moisture sensitive components that may not be used within their exposure time. At one time, we had requested some of our BGA suppliers to reduce the number of parts per reel to reduce the potential for reaching the exposure limit during a production run. Other considerations regarding the decision to go to tape & reel vs. tray packaging is weight of the reel and cost of the reel. In some cases for heavy reels, we experienced feeder advance problems at the beginning of the reel where the advance motor would stall or skip a pitch. As far as cost, you may want to consider how much investment you may have tied up in a single package. I recall one case where a component had a high unit cost and small package size which translated to a cost per reel approaching $500K ! Lastly, we also experienced that large, fine pitch QFPs were vulnerable to lead damage if the tape was twisted due to mis-handling (during loading or unloading). Howard A. Cyker Lucent Technologies New Product Engineering Email [log in to unmask] -----Original Message----- From: Andre Leclair [mailto:[log in to unmask]] Sent: Friday, July 11, 2003 7:55 AM To: [log in to unmask] Subject: Re: [TN] SOT 23 placed upside down Howard When switching over to T/R for Moisture Sensitive Parts (particularily Level 4+) you need to keep in mind your usage QTY's. If small volumes are being used then T/R may not be the way to go (regardless of what the buyers say). The cost savings could easily be lost by the time/labour used to bake/reseal leftover parts. J-STD-033A states that after 1hr exposure, left over parts will need to be resealed or baked to stop further moisture migration and to reset the floor life clock. Look at section 4.1.xx of the J-STD (reseal times with fresh dessicant is 5x's the exposure time(12hr max) for level 2-4 and 10X the exposure (8hr max)for level 5-5A) or bake . Andre Leclair Process Engineer Ansen Corp. --------------------------------------------------- Technet Mail List provided as a free 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/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 1.8e 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------