Gary, Does this spec refer to unconnected pads and should it include thermal reliefs? It does seem over the top to ask for minimum 0.010" clearance on a thermal when it is already connected to the surrounding copper plane. I don't see any problem manufacturing 0.005" clearance on thermal reliefs and would rather have a larger pad to aim for given the choice. However, there must be no unconnected pads with 0.005" clearance and I would agree that 0.010" minimum would be sensible if these are required for some special reason.(Preferably they should be removed but I know some might want to retain them). Question is, can the CAD system distinguish during layout between connected and unconnected pads for different clearances? Regards Paul Gould Teknacron Circuits Ltd In message <[log in to unmask]>, [log in to unmask] writes >Nick > >IPC-D-275 states that the clear area should be no less than 0.010 inch. This >number takes into account the difficulties in etching and the subsequent >inspection of a large copper plane. > >This requirement meets general board manufacturing capabilities . However, >you may be able to find some specialized fabricators that can do better. > >Regards, > >Gary Ferrari >IPC Staff > *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ***************************************************************************