My vendor uses the drill size as the size of the bit. So, if I will made a single sided board (without tin plating nor hot air process) I use one size. Like, for an PTH IC I use 28 mils (0,7 mm) if it is a prototype, and 32 or (better) 36 mils (0,8 and 0,9 mm respec.) for a production board. If I made a double side board with tin plating and hot air I use 32 mils for a prototype board and 36 or 40 mils for production board.
Em Ter 25 Jan 2005 11:45, John Luciani escreveu: > You need to check with your board vendor. > I believe AP circuits treats the value in the drill > file as a drill diameter. It is up to the purchaser > to accommodate for the plating. > > PCB Express uses the value in the drill file as a > finished hole size and they account for the plating > dimensions. This seems like the correct way to do it. > > When I create parts I used the finished hole size. > My PCB file then represents exactly what is required > to create a physically correct board. If I want to > send the board to a different vendor I can post > process > the drill files to accommodate for the differences > in the new process. > > If you adjust your drill sizes you need to be careful > that there is sufficient copper remaining after the > drilling operation to reliably plate (annular ring). > Since most vendors have a wide variety of drill sizes > this should not be a problem. > > (* jcl *) > > --- Wojciech Kazubski <[EMAIL PROTECTED]> wrote: > > > Somebody said that handmade single-sided boards > > > > can use the smaller > > > > > holes. This _may_ be true, but they could also > > > > use the larger holes > > > > > without trouble. The library should be fixed or > > > > removed, not left as > > > > > is with a warning. > > > > > > Matt > > > > Shold the specified diametr be the drill size or > > finished hole size? > > The above values may differ by a few mills or about > > 0.1mm due to plating > > thickness. > > The first is safer, but the second one is less > > technology dependent. > > > > Wojciech Kazubski > > __________________________________ > Do you Yahoo!? > Read only the mail you want - Yahoo! Mail SpamGuard. > http://promotions.yahoo.com/new_mail
