The problem with this workflow when using any version up to and including 5.1.x is the custom fields that you added to your components in the schematic don’t get picked up by PCBNew. No matter how you try to export a BOM from PCBNew, you won’t get the extra fields because PCBNew doesn’t know about them. This is changing for the development nightly releases that will eventually be v6, but that is in the future and not now. There are several BOM exporter scripts in EESchema, you can try them out (watch out, from what I’ve read here, some generate csv files w/o extensions). Or, you can open the
Edit Symbol Fields... from the
Tools menu in EESchema. Here is a screenshot from a stupidly simple board that I use as a scratch-pad:
In this window, using the check-boxes on the left, you can show or hide fields and change what fields are used for grouping. Then CTRL-a to select all and CTRL-c to copy the table to the clipboard (modify the bucky bits
for your OS). Then paste into your favorite spread sheet for further processing (or paste into an empty .csv file using your favorite text editor).
BTW, you never mention what version you are using, so I’m assuming that you are using v5.1.x (currently the latest is 5.1.9 but you may not have updated to that yet, though I would advise doing so to be able to take advantage of all the cumulative bug fixes since 5.1.0 came out). I don’t recall if this trick works in 5.0.x, and I’m positive it won’t in versions that predate 5.0.0.