Hi -- > How often does the need for single-sided boards arise?
The question about single-sided boards is interesting, but the answer depends upon how you intend to fabricate your boards. If you're sending the boards to a PCB manufacturer, then the raw material they use is fiberglass clad with copper on both sides. In this case, it's senseless to ask for a single-sided board to save costs -- they start with a double-sided board in any case. If you're making the PCBs at home, starting with single-sided fiberglass from e.g. Radio Shack, then it's totally sensible to make single sided boards. In this case, just throw away the back side Gerber file. > this kind of > cosmetics with gerber files is an additional error-prone manual step. > Has it been considered to make this an option that is supported by pcb? I agree that it tends to trip up newbies. However, there's one Gerber file per (metal) layer, so you can always discard the back side file without any problems. More to the point: the Gerber, and the related drill file formats are pretty stupid. They don't carry any top-level information about your design. A particular Gerber file knows only about its own layer, and knows nothing about any other layer. The Gerber files have no concept of "stack-up" (i.e. what order the layers are supposed to be stacked in). The drill file only contains information about what drill diameters to use, and where to put the holes. The remaining information, like stack-up, plated vs. non-plated holes, how thick your copper layer should be, how thick your FR-4 should be, desired manufacturing tolerances, etc., are all told to your PCB manufacturer using "fab notes" (i.e. a human-readable text file) and a "fab drawing" (a drawing of the board, stack-up, and other graphical info). Finally, one of the projects slated for work under the Linux Fund's PCB project is to update PCB's handling of layers. Things like the ability to easily deal with single sided boards from inside of PCB are part of the work to be funded by the Linux Fund. I'll just remind everybody that they can make this work happen sooner by making a donation! http://www.linuxfund.org/projects/pcb/ HTH, Stuart _______________________________________________ geda-user mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
