Dear developers at KiCad, I would like to work on implementing backdrill support in KiCad. In this regard, I have thought of 2 possible choices and I need your help in choosing what works best.
*Option 1:* 1. Update via definition to include another sub-type called 'backdrill' 2. Have an additional field in the via definition to have backdrill diameter. 3. Use layer information to indicate what remains after backdrilling. 4. In drill generation, emit one PTH (through hole top to bottom), and either one or two backdrops based on layer information. A backdrill based via would look like following in the s-expression: (via backdrill [(locked)] (at X Y) (size DIAMETER) (drill DIAMETER) (backdrill DIAMETER) (layers LAYER1 LAYER2) [(remove_unused_layers)] [(keep_end_layers)] [(free)] (net NET_NUMBER) (tstamp UUID) ) *Option 2:* Create a new BOARD_ITEM for backdrill which is free-standing and has no direct bearing to vias. S-expression in this case would be something like: (backdrill [(locked)] (at X Y) (drill DIAMETER) (mustnotcut LAYER) (from TOP | BOTTOM) (tstamp UUID) ) In both cases, a tool can be added which detects backdrill worthy vias and prompts addition/cleanup of backdrill for different vias. Any other options? I look forward to your opinions and suggestions in this regard. BTW, as a workaround, currently I am using regular via as backdrill with pad size almost same as the drill size overlaid on the actual via that needs backdrilling. Of course, the backdrill's drill size is made bigger than the pad size of the actual via that needs backdrilling. However, this is not like having native support requires some extra management off hand to indicate what is not plated. Regards, Prasad -- Prasad H L Bhat Chairman and CTO, Astrome Technologies Pvt Ltd (www.astrome.co) -- CONFIDENTIALITY NOTICE: The contents of this email message and any attachments are intended solely for the addressee(s) and may contain confidential and/or privileged information and may be legally protected from disclosure. If you are not the intended recipient of this message or their agent, or if this message has been addressed to you in error, please immediately alert the sender by reply email and then delete this message and any attachments. If you are not the intended recipient, you are hereby notified that any use, dissemination, copying, or storage of this message or its attachments is strictly prohibited. -- You received this message because you are subscribed to the Google Groups "KiCad Developers" group. To unsubscribe from this group and stop receiving emails from it, send an email to devlist+unsubscr...@kicad.org. To view this discussion on the web visit https://groups.google.com/a/kicad.org/d/msgid/devlist/CAJVLBbevzQKCQgzx3%2BDq1mLsC8QgGRGks_Qc92c0Ukw2T%3DkPWA%40mail.gmail.com.