I am a creature of habit. Since tape-up days, I have always created a fab dwg. It is a handy reference dwg for in-house use to double-check hole and board size. Our fab dwgs include the dimensions and hole count table, the layer stack and assignment, and any special notes that differ from our standard specs. I thought all board houses would require a fab dwg for reference to the data they have received. Or do a lot of them assume and go with the data at hand and if made wrong, it is the clients fault! I work very closely with my board houses, so that we both do not cause any problems.
Bob Bauer Sr. Designer Cardinal Scale Mfg. Co. Webb City, Missouri -----Original Message----- From: Abd ul-Rahman Lomax [mailto:[EMAIL PROTECTED]] Sent: Friday, February 22, 2002 10:54 AM To: Protel EDA Forum Subject: Re: [PEDA] DRILL DRAWINGS At 08:18 AM 2/22/2002 -0600, Bob Bauer wrote: >I hear ya! The same problem with graphic symbols. Is there a cure? The cure will leave you in better condition than before you got the disease. The cure is to have Protel print the drill size on the drawing. If one stops and thinks about what a drill drawing is actually used for -- which is not much nowadays, unless one has used the layer for all fab notes, not a bad idea -- I think one will realize that the purpose is better served with the actual drill size being plotted rather than letters or symbols, both of which slow down the reader because they must reference a table. Yes, the drill symbols can interfere with each other, so one must, to make the drawing intelligible, make the symbols small enough that a 1:1 plot would not be readable. But there is no need to *ever* make a 1:1 plot of a drill drawing. The fabricators will use the drill file, not the drill drawing (except for outline and reference locations), which has become, almost completely, only a tool that we can use to visually check what sizes have been assigned. Protel could help us by making drill size display a view option, along with pad numbers and nets. (By the way, drill size accuracy is pretty gross; it is typical that the fabricator has at least 2 mils of deviation from nominal for acceptance. So rounding of drill sizes would be preferred. The fabricator is going to do it anyway, matching the drill sizes in stock. A more sophisticated tool would choose drill sizes by default, taking them back into the PCB database, I won't go into details at this time.) [EMAIL PROTECTED] Abdulrahman Lomax Easthampton, Massachusetts USA * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * To post a message: mailto:[EMAIL PROTECTED] * * To leave this list visit: * http://www.techservinc.com/protelusers/leave.html * * Contact the list manager: * mailto:[EMAIL PROTECTED] * * Forum Guidelines Rules: * http://www.techservinc.com/protelusers/forumrules.html * * Browse or Search previous postings: * http://www.mail-archive.com/[email protected] * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
