Yes. When using auto placement equipment that employs a vision system, and especially surface mount equipment, they provide an excellent reference point for the machinery to determine any skew in the PCB. If there are no fiducial's, a plated through-hole or other pad may be used, but solid pads provide the best contrast for the vision system. In addition, fiducials are usually placed at the far edges of the PCB and thus demonstrate the extremes of any misalignment. Bruce Stilmack GDLS-TO Manufacturing Engineer (850) 574-4773 [log in to unmask] Sivaraja K Chakka <sivaraja_chakka@AG To: [log in to unmask] ILENT.COM> cc: Sent by: TechNet Subject: [TN] <[log in to unmask]> 11/04/2003 06:41 AM Please respond to "TechNet E-Mail Forum."; Please respond to sivaraja_chakka Hi, Can any one explain the necessity of fiducical! Regards Siva --------------------------------------------------- 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 ----------------------------------------------------- --------------------------------------------------- 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 -----------------------------------------------------