The requirement is for a heel fillet only. Side and to fillets are formed to exposed basis metals. While nice to have, they are not required. Heel fillets are required and the specs are listed in IPC-A-610D and J-STD-001D for Class 1, 2 and 3. The focus is on aquiring a good heel fillet, as that is the part of the solder joint that is formed with the finished surface of the lead. Side fillets and toe fillets are suspect, at best, as the solder is forming an intermetallic with oxidized basis metal. -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of James Verrette Sent: Thursday, August 09, 2007 11:54 AM To: [log in to unmask] Subject: [TN] Minimum toe fillet for SOT23-3 land pattern What should be the goal toe fillet for an IPC 7351 land pattern with density level C for a SOT 23 - 3 pin package? (least protrusion, highest density) Jim Verrette Electrical Engineer --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 15.0 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 -----------------------------------------------------