It worked for me! Steven Creswick -----Original Message----- From: Rudy Sedlak [mailto:[log in to unmask]] Sent: Sunday, June 01, 2003 6:25 PM To: [log in to unmask] Subject: Re: [TN] Micro-inch to copper weight conversion... Does anyone except me and Joe Feldstadt remember why we use weight instead of thickness in measuring Copper?? Copper foil used in making printed circuit boards is created by electroplating directly on to a roll, and peeled off as it is formed, thus it never sees a roller. This plating process produces the surface we are all used to seeing on the roll side, but on the plating solution side, the surface is very rough and uneven. This roughness makes it nearly impossible to measure the thickness, as it is different where ever you measure it. So, we use weight, which gives us an average thickness....1 ounce/square foot = 1.3 mils = 1300 microinches. Seems a good way to get around the roughness issue... Anybody got an alternate? Rudy Sedlak RD Chemical Company --------------------------------------------------- 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 -----------------------------------------------------