RE: [TN] (2) Micro-inch to copper weight conversion...Dear conversion makers, I notice here, without checking all of them 2 errors.... Looks like they are reversed 35 micrometer is correct 0.035 nanometer is correct and not Micrometer 0.03556 Nanometer 35.56 Very Best Regards - Roland www.PCBspecialist.com Roland Jaquet - PCBspecialist - 14 ch. de Vers - CH-1228 Plan-Les-Ouates - Geneva - Switzerland - T +41-22-880-0405 - F +41-22-880-0409 - GSM +41-79-203-3723 - Company & Technical Viability - Yield Improvement - Company Strategy & Acquisition - Equipment & Technology Choice - EIPC Member ----- Message d'origine ----- De : paul reid À : [log in to unmask] Envoyé : mardi, 3. juin 2003 23:10 Objet : Re: [TN] (2) Micro-inch to copper weight conversion... There is a range in the thickness measurements of 1-ounce copper and .0014" is on the high side. Often the actual copper measurements are lower. In fact I rarely measure .0014" for 1 ounce copper foil. If the foil measurement is between .0012' - .0014' I conclude that it is 1-ounce copper. For those who pay attention to such things, here are the thicknesses of 1-ounce (0.0014") copper in most measurements of length. Angstrom 355.6 Arpent 6.07638889 E-10 Astronomical unit 2.377005348 E-19 Centimeter 3.556 E -6 Chain 1.767676768 E-9 Cubit (Biblical) 7.777777778 E-8 Decimeter 3.556 E-7 Decameter 3.556 E-9 Fathom 1.944444444 E-8 Fermi 35560000 Fingerbreadth (Biblical) 1.866666667 E-6 Foot 1.166666677 E-7 Furlong 1.767676768 E-10 Hand 3.5 E-7 Handbreadth (Biblical) 4.666666667 E-7 Hectometer 3.556 E-10 Inch 1.4 E-6 Kilometer 3.556 E-11 Kilosparsec 1.152401813 E-27 League 7.365319865 E-12 Light Year 3.758775248 E-24 Link 1.767676768 E-24 Long Foot (Biblical) 6.666666667 E-8 Long Reed (Biblical) 1.111111111 E-8 Megaparsec 1.152401813 E-30 Meter 3.556 E-8 Micrometer 0.03556 Mils 0.0014 Mile 2.2095959596 E-11 Millimeter 3.556 E-5 Nanometer 35.56 Nautical Mile 1.920086393 E-11 Parsec 1.152401813 E-24 Perch 7.070707071 E-9 Pica 8.4 E-6 Planck 2.2225 E-27 Point .0001008 Pole 7.07070707071 E-9 Reed (Biblical) 1.296296296 E-8 Rod 7.070707071 E-9 Span (Biblical) 1.555555556 E-7 Twip 0.0002016 Yard 3.888888889 E-8 A very good share ware program, Master Converter, is available at www.savardsoftware.com. A nice feature of this program is that you can add your own conversions. I, for example, added a copper ounces per square foot to nominal thickness conversion. -----Original Message----- From: Mcmaster, Michael [mailto:[log in to unmask]] Sent: Tuesday, June 03, 2003 12:40 PM To: [log in to unmask] Subject: Re: [TN] (2) Micro-inch to copper weight conversion... Sorry, Mike I have to disagree with you on this. It would be very uncommon to see 1 oz copper at 1.3 mils in a finished board. Almost everyone uses foil that is at the thin end of the spec. Why? Because copper is sold by weight and thinner foil weighs and costs less. IPC 4562 says that ED foils can be 10% below the listed nominal (nominal for 1 oz is 34.3 um or 1.35 mils). Foil more commonly comes in at 1.30 mils or less. Processing does reduce this down to 1.2 or thinner. Remember on the finished board, the copper thickness only needs to be 1.0 mils. Mike McMaster RF Product Engineer Merix Corporation 503-992-4263 ---------- From: Barmuta, Mike[SMTP:[log in to unmask]] Reply To: TechNet E-Mail Forum.;Barmuta, Mike Sent: Tuesday, June 03, 2003 7:19 AM To: [log in to unmask] Subject: Re: [TN] (2) Micro-inch to copper weight conversion... Robert: Fascinating story about ivory PCB's, never heard that one before. I think there needs to be some clarification on the thickness of 1oz Cu foil. It may start out at 1.4 mils but it ends up at about 1.3 mils due to processing steps such as deburring and microetch. So in the real world, the boards Steve was questioning that were fabricated using 1oz foil should have a FINISHED Cu foil thickness of 1.3 mils after conventional processing. Regards Michael Barmuta Staff Engineer Fluke Corp. Everett Wa 425-446-6076 -----Original Message----- From: Robert Tarzwell [mailto:[log in to unmask]] Sent: Monday, June 02, 2003 4:37 PM To: [log in to unmask] Subject: Re: [TN] Micro-inch to copper weight conversion... This just goes to show how old I am but when we first started to manufacture printed circuit boards the only copper you could buy was a very thin sheet the roofers used to solder flashes around wondows and stuff it was 2 oz copper and thats how it was sold by the oz. then the lamianted manufatures started to make laminate I think GE was first, or thats who we got, So even though theres lots of replies it all started with the available copper of the day. early 1960's Not realy connected but my grandfather told me about making a sort of printed board in the 20's by using IVORY and drawing lines between copper rivets with carbon black in wavy lines to make resistors. Robert tarzwell PS some replies have the thickness of 1 oz of copper incorect it is closer to 1.39 mils. not 1.3 --------------------------------------------------- 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 ----------------------------------------------------- --------------------------------------------------- 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 ----------------------------------------------------- --------------------------------------------------- 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 -----------------------------------------------------