I wouldn't advise "designing" in a 5mil thermal relief or anti-pad. It can be done, but for a price. For a 1oz copper layer, I design a 8mil thermal/anti to guarentee 6mils. The fab shop needs some room to "enhance" the copper areas, be it the pad or the trace, if you "design" in a 5mil spacing and your anular ring on your pads is at min., along with a conductor track at finished size, you leave no room for your vendor to "beef-up" those areas to guarentee your final requirements. My question to you is, why so tight? You could also "remove" all unused pads on each layer, this would give you more relief between signal and ground/pwr. Bottom line, if you NEED it, do it. It will cost you in lower yeilds, lower yeilds = $$$. Talk to your vendor. Dan Lorinser BFGoodrich Aerospace Burnsville, MN >>> Wander, Nicholas G RV <[log in to unmask]> Jan 29, 1997 7:41 pm >>> Is a .005 inch gap width (the width of the "no copper" areas) for small thermal reliefs a problem? Can this be etched in 1 oz. copper without major difficulties? Nick Wander Printed Circuit Engineering Unisys Corp. Roseville, MN. *************************************************************************** * 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] * *************************************************************************** *************************************************************************** * 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] * ***************************************************************************