Hi Designers Most PCB manufacturers work with boardclasses that differ in parameters e.g. minimum feature size, minimum annular ring etc. Yields and thus prices vary between classses, that's basically why they exist. In most cases the parameters are inter-related though : normally you don't use 0.010" holes in a 0.02"/0.02" technology. Now does anyone know of a piece of software that will derive all parameters from a minimum set automatically ? (the next step would be that you write a postprocessor that will import all parameter values into the CAD system, effectively defining the set of designrules). Best regards, Peter Willaert Agfa-Gevaert N.V. [log in to unmask] ############################################################## IPC Designers Council Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE DESIGNERCOUNCIL <your full name> To unsubscribe: SIGNOFF DESIGNERCOUNCIL ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ##############################################################