Hi Franklin, Our granite surface plate is used strictly for warp & twist measurement of pcb's (very light use). It's on our recall list. The calibration is rather expensive. I was able to move from yearly cal to 3 year cal by downgrading the plate from "A" (inspection grade) to "B" (shop grade, I believe) which is still well within our accuracy requirements. Regards, Mark Hargreaves -----Original Message----- From: Franklin D Asbell [SMTP:[log in to unmask]] Sent: Thursday, January 30, 2003 10:57 AM To: [log in to unmask] Subject: [TN] Calibration/Verification of granite-surface block Can anyone describe to me the method of calibrating/verifying a surface block??? Also, in regards to calibration recall, would this need to be on a recall list or would it be verify it once in it's lifetime, what would be a cause of initial calibration being voided... Thanks, Franklin D Asbell --------------------------------------------------- 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 -----------------------------------------------------