> I understand that I'm specifying a drill size, It depends on the fab. 4pcb, for example, wants finished size because only they know how their specific process for that board will affect finished hole size. Others want drill size, and tell you 0.1mm for barrel thickness (2x = hole shrinkage), etc.
> and I'll lose about 3mil in finished hole diameter from the plating. It depends on the process. > If I look at a manufacturer recommended PCB layout and it calls for a > hole dimension, do I bulk that up, or keep it? It depends on the fab. Yes, I'm repeating myself, because it does. The spec wants a finished hole size. If your fab wants finished hole size, give them the size you want. If it's drill size, see how much they want you to oversize it. Also, you need 5 mil for solder wicking. > It looks like they're taking it into account, but I'd hate to make a > board with holes too small for my connectors... When I do a board here (no plating), I use smaller than average drills so that the parts stay still when I put them in. It also allows for sloppier drill alignment. _______________________________________________ geda-user mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
